SUMMARY

From November 2022 through early January 2023, the Cybersecurity and Infrastructure Security Agency (CISA) and authoring organizations identified the presence of indicators of compromise (IOCs) at a federal civilian executive branch (FCEB) agency. Analysts determined that multiple cyber threat actors, including an APT actor, were able to exploit a .NET deserialization vulnerability (CVE-2019-18935) in Progress Telerik user interface (UI) for ASP.NET AJAX, located in the agency’s Microsoft Internet Information Services (IIS) web server. Successful exploitation of this vulnerability allows for remote code execution. According to Progress Software, Telerik UI for ASP.NET AJAX builds before R1 2020 (2020.1.114) are vulnerable to this exploit.[1]

Actions to take today to mitigate malicious cyber activity:

• Implement a patch management solution to ensure compliance with the latest security patches.
• Validate output from patch management and vulnerability scanning against running services to check for discrepancies and account for all services.
• Limit service accounts to the minimum permissions necessary to run services.

CISA, the Federal Bureau of Investigation (FBI), and the Multi-State Information Sharing and Analysis Center (MS-ISAC) are releasing this joint Cybersecurity Advisory (CSA) to provide IT infrastructure defenders with tactics, techniques, and procedures (TTPs), IOCs, and methods to detect and protect against similar exploitation.

Download the PDF version of this report:

For a downloadable copy of IOCs, see

TECHNICAL DETAILS

Note: This advisory uses the MITRE ATT&CK® for Enterprise framework, version 12. See the MITRE ATT&CK Tactics and Techniques section for a table of the threat actors’ activity mapped to MITRE ATT&CK tactics and techniques with corresponding detection and mitigation recommendations.

Overview

CISA and authoring organizations assess that, beginning as late as November 2022, threat actors successfully exploited a .NET deserialization vulnerability (CVE-2019-18935) in an instance of Telerik UI for ASP.NET AJAX Q2 2013 SP1 (version 2013.2.717) running on an FCEB agency’s Microsoft IIS server. This exploit, which results in interactive access with the web server, enabled the threat actors to successfully execute remote code on the vulnerable web server. Though the agency’s vulnerability scanner had the appropriate plugin for CVE-2019-18935, it failed to detect the vulnerability due to the Telerik UI software being installed in a file path it does not typically scan. This may be the case for many software installations, as file paths widely vary depending on the organization and installation method.

In addition to CVE-2019-18935, this version (2013.2.717) of Telerik UI for ASP.NET AJAX contains the following known vulnerabilities: CVE-2017-11357, CVE-2017-11317, and CVE-2017-9248. Analysis suggests that cyber threat actors exploited CVE-2019-18935 in conjunction with either CVE-2017-11357 or CVE-2017-11317. Australian Cyber Security Centre (ACSC) Advisory 2020-004 assesses that exploitation of CVE-2019-18935 is only possible with knowledge of Telerik RadAsyncUpload encryption keys.[2] Threat actors can obtain these keys through either prior knowledge or exploitation of vulnerabilities—CVE-2017-11357 or CVE-2017-11317—present in older, unpatched versions of Telerik released between 2007 and 2017. Forensic evidence is not available to definitively confirm exploitation of either CVE-2017-11357 or CVE-2017-11317.

Threat Actor Activity

CISA and authoring organizations observed multiple cyber threat actors, including an APT actor—hereafter referred to as Threat Actor 1 (TA1)—and known cybercriminal actor XE Group—hereafter referred to as Threat Actor 2 (TA2)—conducting reconnaissance and scanning activities [T1595.002] that correlate to the successful exploitation of CVE-2019-18935 in the agency’s IIS server running Telerik UI for ASP.NET AJAX [T1190].

When exploiting the vulnerability, the threat actors uploaded malicious dynamic-link library (DLL) files (some masqueraded as portable network graphics [PNG] files) [T1105] to the C:WindowsTemp directory. The malicious files were then executed from the C:WindowsTemp directory via the w3wp.exe process—a legitimate process that runs on IIS servers. This process is routine for handling requests sent to web servers and delivering content. The review of antivirus logs identified that some DLL files were created [T1055.001] and detected as early as August 2021.

CISA and authoring organizations confirmed that some malicious files dropped on the IIS server are consistent with a previously reported file naming convention that threat actors commonly use when exploiting CVE-2019-18935.[3] The threat actors name the files in the Unix Epoch time format and use the date and time as recorded on the target system. The file naming convention follows the pattern [10 digits].[7 digits].dll (e.g., a file created on October 31, 2022, could be 1667203023.5321205.dll).

The names of some of the PNG files were misleading. For example, file 1596835329.5015914.png, which decodes to August 7, 2020, 21:22:09 UTC, first appeared on October 13, 2022, but the file system shows a creation date of August 7, 2020. The uncorrelated Unix Epoch time format may indicate that the threat actors used the timestomping [T1070.006] technique. This file naming convention is a primary IOC used by the threat actors.

In many cases, malicious artifacts were not available for analysis because the threat actors’ malware—that looks for and removes files with the .dll file extension—removed files [T1070.004] from the C:WindowsTemp directory. Through full packet data capture analysis and reverse engineering of malicious DLL files, no indications of additional malicious activity or sub-processes were found executed by the w3wp.exe process. CISA observed error messages being sent to the threat actors’ command and control (C2) server when permission restraints prevented the service account from executing the malicious DLLs and writing new files.

Network activity analysis was consistent with the artifacts provided for review. Analysts did not observe evidence of privilege escalation or lateral movement.

Threat Actor 1

CISA and authoring organizations observed TA1 exploiting CVE-2019-18935 for system enumeration beginning in August 2022. The vulnerability allows a threat actor to upload malicious DLLs on a target system and execute them by abusing a legitimate process, e.g., the w3wp.exe process. In this instance, TA1 was able to upload malicious DLL files to the C:WindowsTemp directory and then achieve remote code execution, executing the DLL files via the w3wp.exe process.

At least nine DLL files used for discovery [TA0007], C2 [TA0011], and defense evasion [TA0005]. All of the analyzed samples have network parameters, including host name, domain name, Domain Name System (DNS) server Internet Protocol (IP) address and machine name, Network Basic Input/Output System (NetBIOS) ID, adapter information, IP address, subnet, gateway IP, and Dynamic Host Configuration Protocol (DHCP) server [T1016]. All analyzed samples communicate this collected data to a C2 server at IP address 137.184.130[.]162 or 45.77.212[.]12. The C2 traffic to these IP addresses uses a non-application layer protocol [T1095] by leveraging Transmission Control Protocol (TCP) clear text (i.e., unencrypted) over port 443. Analysis also identified that:

• Some of the analyzed samples can load additional libraries; enumerate the system, processes, files, directories [T1083]; and write files.
• Other analyzed samples can delete DLL files ending with the .dll extension in the C:WindowsTemp directory on the server. TA1 may use this capability to hide additional malicious activity on the network.

CISA, in coordination with the authoring organizations, identified and observed the following threat actor IPs and timestamps associated with this activity:

Table 1: Observed TA1 IPs and Timestamps

IP Address	First Identified	Last Identified
137.184.130[.]162	09/26/2022	10/08/2022
45.77.212[.]12	10/07/2022	11/25/2022
104.225.129[.]102	10/10/2022	11/16/2022
149.28.85[.]24	10/12/2022	10/17/2022
185.186.245[.]72	10/18/2022	10/18/2022
193.8.172[.]113	09/25/2022	09/25/2022
193.8.172[.]13	09/25/2022	10/17/2022
216.120.201[.]12	10/13/2022	11/10/2022
5.34.178[.]246	09/25/2022	09/25/2022
79.133.124[.]242	09/25/2022	09/25/2022
92.38.169[.]193	09/27/2022	10/08/2022
92.38.176[.]109	09/12/2022	09/25/2022
92.38.176[.]130	09/25/2022	10/07/2022

Threat Actor 2

TA2—identified as likely the cybercriminal actor XE Group—often includes xe[word] nomenclature in original filenames and registered domains. Volexity lists this naming convention and other observed TTPs as common for this threat actor group.[4]

As early as August 2021, CISA and authoring organizations observed TA2 delivering malicious PNG files that, following analysis, were masqueraded DLL files to avoid detection [T1036.005]. Similar to TA1, TA2 exploited CVE-2019-18935 and was able to upload at least three unique DLL files into the C:WindowsTemp directory that TA2 executed via the w3wp.exe process. These DLL files drop and execute reverse (remote) shell utilities for unencrypted communication with C2 IP addresses associated with the malicious domains listed in Table 2. Note: At the time of analysis, the domains resolved to the listed IP addresses.

Table 2: TA2 IPs and Resolving Domains

IP Address	Resolving Domains
184.168.104[.]171	xework[.]com xegroups[.]com hivnd[.]com
144.96.103[.]245	xework[.]com

Analysis of DLL files determined the files listed in Table 3 were dropped, decoded, and attempted to connect to the respective malicious domains. Embedded payloads dropped by the DLL files were observed using the command line utility certutil[.]exe and writing new files as xesvrs[.]exe to invoke reverse shell utilities execution.

Table 3: Identified Malicious Files

Filename	Description
XEReverseShell.exe	DLL files (masqueraded as PNG files) located in the C:WindowsTemp directory contain a base64 encoded file with the internal name XEReverseShell.exe, which was dropped into the same directory as sortcombat.exe. When executed, the reverse shell utility attempts to connect to xework[.]com or xegroups[.]com to obtain the IP address of the C2 server and port number for unencrypted communication. Note: It is likely the threat actors changed the file extension from .dll to .png to avoid detection.
Multi-OS_ReverseShell.exe	Reverse shell utility decoded from the base64 encoded file xesmartshell.tmp. When executed, it will attempt to connect to xegroups[.]com or xework[.]com to obtain the IP address of the C2 server and port number for unencrypted communication.
SortVistaCompat	Base64 encoded payload dropped from Multi-OS_ReverseShell.exe. This file receives the C2 IP and port from xework[.]com.

 When the TA2 malware is executed a DLL file drops an executable (XEReverseShell.exe) that attempts to pull a C2 IP address and port number from xework[.]com or xegroups[.]com.

• If no port or IP address is found, the program will exit.
• If a port and IP address are found, the program will establish a listener and wait for further commands.

If communication is established between the TA2 malware and the C2:

• The malware will identify the operating system (Windows or Linux) and create the appropriate shell (cmd or bash), sending system information back to the C2.
• The C2 server may send the command xesetshell, causing the malware to connect to the server and download a file called small.txt—a base64-encoded webshell that the malware decodes and places in the C:WindowsTemp directory.
• The C2 server may send the command xequit, causing the malware to sleep for a period of time determined by the threat actors.

The two files xesmartshell.tmp and SortVistaCompat have the capability to drop an Active Server Pages (ASPX) webshell—a base64 encoded text file small.txt decoded [T1140] as small.aspx [T1505.003]—to enumerate drives; to send, receive, and delete files; and to execute incoming commands. The webshell contains an interface for easily browsing files, directories, or drives on the system, and allows the user to upload or download files to any directory. No webshells were observed to be dropped on the target system, likely due to the abused service account having restrictive write permissions.

For more information on the DLLs, binaries, and webshell, see CISA MAR-10413062-1.v1 Telerik Vulnerability in U.S. Government IIS Server.

MITRE ATT&CK TACTICS AND TECHNIQUES

See Table 4 for all referenced threat actor tactics and techniques in this advisory. For assistance with mapping to the MITRE ATT&CK framework, see CISA’s Decider Tool and Best Practices for MITRE ATT&CK Mapping Guide.

Table 4: Identified ATT&CK Techniques for Enterprise

Reconnaissance
Technique Title	ID	Use
Active Scanning: Vulnerability Scanning	T1595.002	Actors were observed conducting active scanning activity for vulnerable devices and specific ports.
Initial Access
Technique Title	ID	Use
Exploit Public-Facing Application	T1190	Actors exploited a known vulnerability in the Microsoft IIS server.
Persistence
Technique Title	ID	Use
Server Software Component: Web Shell	T1505.003	TA2’s malware dropped an ASPX webshell to enumerate drives; send, receive, and delete files; and execute commands.
Defense Evasion
Technique Title	ID	Use
Masquerading: Match Legitimate Name or Location	T1036.005	Actors leveraged the legitimate w3wp.exe process on the IIS server to write malicious DLL files and evade detection.
Process Injection: DLL Injection	T1055.001	Actors loaded newly created DLLs into a running w3wp.exe process.
Indicator Removal: File Deletion	T1070.004	TA1’s malware deleted files with “.dll” from the C:WindowsTemp directory, which may indicate hidden malicious activity on the network.
Indicator Removal: Timestomp	T1070.006	Actors modified file time attributes to insert misleading creation dates.
Decode Files	T1140	The base64 encoded text file small.txt decoded as the webshell small.aspx.
Discovery
Technique Title	ID	Use
File and Directory Discovery	T1083	Actors enumerated the IIS server via OS fingerprinting, executed Windows processes, and collected network information. TA1’s malware enumerates systems, processes, files, and directories.
System Network Configuration Discovery	T1016	TA1’s malware gathers network parameters, including host name, domain name, DNS servers, NetBIOS ID, adapter information, IP address, subnet, gateway IP, and DHCP server.
Command and Control
Technique Title	ID	Use
Ingress Tool Transfer	T1105	TA1 and TA2 uploaded malicious DLL files (some masqueraded as PNG files) to the C:WindowsTemp directory.
Non-Application Layer Protocol	T1095	Actors used a non-application layer protocol (TCP) for w3wp.exe process exploitation, C2, and enumeration on the IIS server.

DETECTION METHODS

CISA and authoring organizations recommend that organizations review the steps listed in this section and Table 4: Identified ATT&CK Techniques for Enterprise to detect similar activity on IIS servers.

Yara Rule

CISA developed the following YARA rule from the base proof-of-concept code for CVE-2019-18935.[5] Note: Authoring organizations do not guarantee all malicious DLL files (if identified) will use the same code provided in this YARA rule.

rule CISA_10424018_01 {
meta:
        Author = "CISA Code & Media Analysis"
        Incident = "10424018"
        Date = "2023-02-07"
        Last_Modified = "20230216_1500"
        Actor = "n/a"
        Family = "n/a"
        Capabilities = "n/a"
        Malware_Type = "n/a"
        Tool_Type = "n/a"
        Description = "Detects open-source exploit samples"
        SHA256 = "n/a"
    strings:
        $s0 = { 3D 20 7B 20 22 63 6D 22 2C 20 22 64 2E 65 22 2C }
        $s1 = { 20 22 78 22 2C 20 22 65 22 20 7D 3B }
        $s2 = { 52 65 76 65 72 73 65 53 68 65 6C 6C 28 29 }
        $s3 = { 54 65 6C 65 72 69 6B 20 55 49 }
        $s4 = { 66 69 6C 65 6E 61 6D 65 5F 6C 6F 63 61 6C }
        $s5 = { 66 69 6C 65 6E 61 6D 65 5F 72 65 6D 6F 74 65 }
        $s6 = { 41 55 43 69 70 68 65 72 2E 65 6E 63 72 79 70 74 }
        $s7 = { 31 32 31 66 61 65 37 38 31 36 35 62 61 33 64 34 }
$s8 = { 43 6F 6E 6E 65 63 74 53 74 61 67 69 6E 67 53 65 72 76 65 72 28 29 }
        $s9 = { 53 74 61 67 69 6E 67 53 65 72 76 65 72 53 6F 63 6B 65 74 }
        $s10 = { 2A 62 75 66 66 65 72 20 3D 20 28 75 6E 73 69 67 6E 65 }
$s11 = { 28 2A 29 28 29 29 62 75 66 66 65 72 3B 0A 20 20 20 20 66 75 6E 63 28 29 3B }
$s12 = { 75 70 6C 6F 61 64 28 70 61 79 6C 6F 61 64 28 54 65 6D 70 54 61 72 67 65 74 }
        $s13 = { 36 32 36 31 36 66 33 37 37 35 36 66 32 66 }
    condition:
($s0 and $s1 and $s2) or ($s3 and $s4 and $s5 and $s6 and $s7) or ($s8 and $s9 and $s10 and $s11) or ($s12 and $s13)
}

Log Collection, Retention, and Analysis

CISA, FBI, and MS-ISAC recommend that organizations utilize a centralized log collection and monitoring capability, as well as implement or increase logging and forensic data retention. Longer retention policies improve the availability of data for forensic analysis and aid thorough identification of incident scope.

• Centralized log collection and monitoring allows for the discovery of webshell and other exploit activity. For example, organizations should monitor for external connections made from the IIS server to unknown external IP addresses. Logging may also be available—if enabled at the router or firewall—for any outbound connections initiated with PowerShell.
• Access- and security-focused firewall (e.g., Web Application Firewall [WAF]) logs can be collected and stored for use in both detection and forensic analysis activities. Organizations should use a WAF to guard against publicly known web application vulnerabilities, in addition to guarding against common web application attacks.

Creation of Malicious DLLs

CISA, FBI, and MS-ISAC recommend that organizations use process monitoring—which provides visibility into file system and application process activity—to detect suspicious executable files running from the C:WindowsTemp directory. Process monitoring via Windows Event Code 4688 will detect the legitimate w3wp.exe process running suspicious DLL files and other anomalous child processes. Note: Enabling this event may inundate security event logging. Use centralized log collection to prevent log rollover, increase log retention and archiving, and/or enable command line event logging.

Forensic analysis commonly identified the threat actors taking the following steps:

1. Create one of the DLL files (C:WindowsTemp1665890187.8690152.dll) by process w3wp.exe PID 6484.
2. Load the newly created DLL into a currently running IIS process, w3wp.exe PID 6484. 
3. Make a TCP connection using w3wp.exe PID 6484 to 45.77.212[.]12 over port 443.
4. Invoke C:WindowsSystem32vcruntime140.dll (Windows C runtime library) to execute payload.

Steps 1 and 2 occur every time a malicious DLL file is created. In some cases, an ASP .NET temp file was created, but this may have indicated benign IIS server activity. Note: The Process ID (PID) used in this example is unique to this investigation and is not universal. IP address 45.77.212[.]12 correlates to TA1, but the pattern can be used as general practice to identify similar activity.

Additional Searching for IIS Servers

The following information was derived from artifact analysis and is provided to equip IT infrastructure defenders searching for similar activity on an IIS server. Several artifacts can be referenced to assist in determining if CVE-2019-18935 has been successfully exploited.

File Type: DLL

Location: – %SystemDrive%WindowsTemp

When this CVE is exploited, it uploads malicious DLL files to the C:WindowsTemp directory. The malicious DLL file naming convention translates to the exact time the file was uploaded to the server.

The time is represented in a series of digits, known as Unix Epoch time. The files observed during this investigation contained two sets of digits separated by a period (.) before the DLL extension (.dll). Example: 1667206973.2270932.dll

Nearly all recovered files contain a series of 10 digits to the left of the period (.) and seven digits to the right. However, one file contained only five digits in the second set, which should be taken into consideration when writing regex patterns to search for the existence of these files. Example Regex: d{10}.d{1,8}.dll

These numbers can be copied and translated from digits into readable language with the month, day, year, hour, minute, and seconds displayed.

Log Type: IIS

Location: – %SystemDrive%inetpublogsLogFiles

When investigating IIS logs, specific fields were searched for and captured during the time of each connection.

If the Unix Epoch time signature has been translated from a DLL filename, specific logs can be searched based on that time. However, if the Unix Epoch time signature has not been translated, the following will still work, but may take longer for the query to run.

The four most important fields to identify this traffic are noted in the following table. These descriptions are sourced directly from Microsoft.[6]

Table 5: Four Fields Searched in IIS Logs

General Name	Field Name	Description
Method	cs-method	Requested action; for example, a GET method
URI Stem	cs-uri-stem	Universal Resource Identifier (URI), or target, of the action
URI Query	cs-uri-query	The query, if any, that the client was trying to perform; A URI query is necessary only for dynamic pages.
Protocol Status	sc-status	Hypertext Transfer Protocol (HTTP) or File Transfer Protocol (FTP) status code

Note: Depending on how logs are collected and stored, the field names may not be an exact match; this should be taken into consideration when constructing queries.

When ingesting logs into security information and event management (SIEM), the final field names did not use a hyphen (-) but used an underscore (_).

Example: cs_method instead of cs-method

Artifacts:

Table 6: Information Contained in Two Observed IIS Events

Field Name	Artifact
cs-method	POST
>cs-uri-stem	/Telerik.Web.UI.WebResource.axd
cs-uri-query	type=rau
sc-status	200 and 302

When reviewing logs, two IIS events were observed with the same timestamp each time this CVE-2019-18935 was exploited. Both events contained the same information in the cs-method, cs-uri-stem, and cs-uri-query. One event had a sc-status of 200 and the other had a sc-status of 302.

Log Type: Windows Event Application Logs

Location: -%SystemDrive%WindowsSystem32winevtlogsApplication.evtx

Kroll Artifact Parser and Extractor (KAPE), a forensic artifact collector and parser, was used to extract the Windows event logs from a backup image of the compromised IIS server. All field names refer to the labels provided via KAPE exports. The strings are of value and can be used to locate other artifacts if different tools are used. Note: The payload data in the following table has been shortened to only necessary strings to obscure and protect victim information.

Table 7: Example Payload Data

EventID

Payload

1309

3005, An unhandled exception has occurred[*redacted*]w3wp.exe[*redacted*]InvalidCastException, Unable to cast object of type ‘System.Configuration.Install.AssemblyInstaller’ to type ‘Telerik.Web.UI.IAsyncUploadConfiguration’.n at Telerik.Web.UI.AsyncUploadHandler.GetConfiguration(String rawData)n at Telerik.Web.UI.AsyncUploadHandler.EnsureSetup()n at Telerik.Web.UI.AsyncUploadHandler.ProcessRequest(HttpContext context)n at Telerik.Web.UI.HandlerRouter.ProcessHandler(String handlerKey, HttpContext context)n at Telerik.Web.UI.WebResource.ProcessRequest(HttpContext context)n at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()n at System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step)n at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)nn, [*redacted*]/Telerik.Web.UI.WebResource.axd?type=rau, /Telerik.Web.UI.WebResource.axd, [*redacted*], False, [*redacted*], 15, [*redacted*], False, at Telerik.Web.UI.AsyncUploadHandler.GetConfiguration(String rawData)n at Telerik.Web.UI.AsyncUploadHandler.EnsureSetup()n at Telerik.Web.UI.AsyncUploadHandler.ProcessRequest(HttpContext context)n at Telerik.Web.UI.HandlerRouter.ProcessHandler(String handlerKey, HttpContext context)n at Telerik.Web.UI.WebResource.ProcessRequest(HttpContext context)n at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()n at System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step)n at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)n”,”Binary”:””}}

Authoring organizations recommend looking for the following key strings in the payload:

• w3wp.exe: This is the parent process that executes the code inside the malicious DLLs.
• System.Configuration.Install.AssemblyInstaller: Figure 1 is from the creator’s GitHub repo,[7] where the string can be observed in the code. As presented by Bishop Fox and proven during authoring organizations’ investigation of IIS server logs, an exception does not mean that the exploit failed, but more likely that it executed successfully.[3]

If a Werfault crash report was written, Windows event application logs may contain evidence of this— even if the DLLs have been removed from the system as part of a cleanup effort by the threat actors.

Table 8: Example Threat Actor Cleanup

EventID	ExecutableInfo	MapDescription	Payload
1000	w3wp.exe |1664175639.65719.dll |c:windowssystem32inetsrvw3wp.exe |C:WindowsTemp1664175639.65719.dll	Application Error	{“EventData”:{“Data”:”w3wp.exe, 8.5.9600.16384, 5215df96, 1664175639.65719.dll, 0.0.0.0, 63314d94, c00000fd, 00000000000016f8, 1708, 01d8d0a5f84af443, c:\windows\system32\inetsrv\w3wp.exe, C:\Windows\Temp\1664175639.65719.dll, eed89eeb-3d68-11ed-817c-005056990ed7″,”Binary”:””}}
1001	w3wp.exe |1664175639.65719.dll |C:ProgramDataMicrosoftWindowsWERReportQueueAppCrash_w3wp.exe |C:ProgramDataMicrosoftWindowsWERReportQueueAppCrash_w3wp.exe |C:ProgramDataMicrosoftWindowsWERReportQueueAppCrash_w3wp.exe	Application Crash	{“EventData”:{“Data”:”0, APPCRASH, Not available, 0, w3wp.exe, 8.5.9600.16384, 5215df96, 1664175639.65719.dll, 0.0.0.0, 63314d94, c00000fd, 00000000000016f8, nC:\Windows\Temp\WERE3F6.tmp.appcompat.txtnC:\Windows\Temp\WERE639.tmp.WERInternalMetadata.xmlnC:\ProgramData\Microsoft\Windows\WER\ReportQueue\AppCrash_w3wp.exe_d538da447d49df5862c37684118d0c25c2eff_9e3fd63b_cab_0c3ee656\memory.hdmpnC:\ProgramData\Microsoft\Windows\WER\ReportQueue\AppCrash_w3wp.exe_d538da447d49df5862c37684118d0c25c2eff_9e3fd63b_cab_0c3ee656\triagedump.dmp, C:\ProgramData\Microsoft\Windows\WER\ReportQueue\AppCrash_w3wp.exe_d538da447d49df5862c37684118d0c25c2eff_9e3fd63b_cab_0c3ee656, 0, eed89eeb-3d68-11ed-817c-005056990ed7, 4″,”Binary”:””}}

The EventID field maps to Windows EventIDs for an easy filter. Users can leverage the Windows EventIDs to find malicious DLL with the Unix Epoch time-based name inside the C:WindowsTemp directory.

Depending how log analysis is performed, various filters can be determined. However, if regex is available, the example listed in Table 8 above can be reused to match the Unix Epoch timestamp convention to assist in filtering.

Additional Analysis

When evidence of malicious DLLs is found, reverse engineering will need to be conducted to fully understand what actions occur as the malicious files could do nearly anything. Leveraging Windows security event logs, as well as Windows PowerShell logs, may provide insight into what actions the DLLs are taking. CISA and authoring organizations recommend the following process:

1. Convert any discovered malicious DLL timestamps to readable format.
2. Export the Windows security event and PowerShell logs from the device.
   • Default path: %SystemDrive%WindowsSystem32winevtlogsWindows PowerShell
   • Default path: %SystemDrive%WindowsSystem32winevtlogsSecurity.evtx
3. Filter based on identified timestamps.
4. Search for new processes created via w3wp.exe in Windows security event logs (e.g., Windows EventID 4688 New Process created).
5. Search for new PIDs from identified events. Investigate to determine if they spawned any other processes.
   • Example: CMD.EXE launching PowerShell or running other commands such as nslookup or netstat. Note: This is not an exhaustive list.
6. Search for EventID 600 in PowerShell logs.

Trellix XDR Platform Searching

If Trellix XDR Platform is deployed in an environment and a standard HX triage audit is completed in a timely manner of the suspected use of CVE-2019-18935, an organization can search for file write events from known web processes. This will identify the executables written by the web server process. CISA and authoring organizations specifically recommend searching for the following field value pair:

Table 9: Field Value Pair for Searching

Field	Value Begins With
TextAtLowestOffset	MZ

MITIGATIONS

Note: These mitigations align with the Cross-Sector Cybersecurity Performance Goals (CPGs) developed by CISA and the National Institute of Standards and Technology (NIST). The CPGs provide a minimum set of practices and protections that CISA and NIST recommend all organizations implement. CISA and NIST based the CPGs on existing cybersecurity frameworks and guidance to protect against the most common and impactful threats, tactics, techniques, and procedures. Visit CISA’s Cross-Sector Cybersecurity Performance Goals for more information on the CPGs, including additional recommended baseline protections.

Manage Vulnerabilities and Configurations

• Upgrade all instances of Telerik UI ASP.NET AJAX to the latest version after appropriate testing. Keep all software up to date and prioritize patching to known exploited vulnerabilities (KEVs). [CPG 5.1]
• Prioritize remediation of vulnerabilities on internet-facing systems. For additional guidance, see CISA Insights – Remediate Vulnerabilities for Internet-Accessible Systems. [CPG 5.1]
• Implement a patch management solution to ensure compliance with the latest security patches. A patch management solution that inventories all software running in addition to vulnerability scanning is recommended.
• Ensure vulnerability scanners are configured to scan a comprehensive scope of devices and locations. For example, as noted in the Technical Details section, the victim organization had the appropriate plugin for CVE-2019-18935, but the vulnerability went undetected due to the Telerik UI software being installed in a file path not typically scanned. To identify unpatched instances of software vulnerabilities, organizations using vulnerability scanners should be aware that all installations may not be considered “typical” and may require full file scans of web applications.
  • Note: Vulnerability scanners may have limitations in detecting vulnerabilities, such as only being able to identify Windows Installer-installed applications, which was the case with this agency’s vulnerability scanner. The Telerik UI software was installed via a continuous integration (CI) and continuous delivery (CD) pipeline rather than the Windows Installer. This highlights the importance of using a comprehensive approach for vulnerability scanning that considers all potential installation methods and file paths.
• Validate output from patch management and vulnerability scanning solutions against running services to check for discrepancies and account for all services.

 Segment Networks Based on Function

• Implement network segmentation to separate network segments based on role and functionality. Proper network segmentation significantly reduces the ability for threat actor lateral movement by controlling traffic flows between—and access to—various subnetworks. (See CISA’s Layering Network Security Through Segmentation infographic and the National Security Agency’s Segment Networks and Deploy Application-Aware Defenses.) [CPG 8.1]
• Isolate similar systems and implement micro-segmentation with granular access and policy restrictions to modernize cybersecurity and adopt zero trust principles for both network perimeter and internal devices. Logical and physical segmentation are critical to limiting and preventing lateral movement, privilege escalation, and exfiltration. Utilize access control lists (ACLs), hardened firewalls, and network monitoring devices to regulate, monitor, and audit cross-segment access and data transfers.

Other Best Practice Mitigation Recommendations

• Implement phishing-resistant multifactor authentication (MFA) for as many services possible—particularly for webmail, virtual private networks (VPNs), accounts that access critical systems, and privileged accounts that manage backups.
  • MFA can still be leveraged for secure access using a jump server—an asset placed between the external and internal networks that serves as an intermediary for access—to facilitate connections if assets do not have the capability to support MFA implementation.
  • For additional guidance on secure MFA configurations, visit cisa.gov/mfa. [CPG 1.3]
• Monitor and analyze activity logs generated from Microsoft IIS and remote PowerShell. Collect access and security focused logs (IDS/IDPS, firewall, DLP, VPN) and ensure logs are securely stored for a specified duration informed by risk or pertinent regulatory guidance. [CPG 3.1, 3.2]
  • Evaluate user permissions and maintain separate user accounts for all actions and activities not associated with the administrator role, e.g., for business email, web browsing, etc. All privileges should be reevaluated on a recurring basis to validate continued need for a given set of permissions. [CPG 1.5]
• Limit service accounts to the minimum permissions necessary to run services. CISA observed numerous error messages in network logs indicative of failed attempts to write files to additional directories or move laterally.
• Maintain a robust asset management policy through comprehensive documentation of assets, tracking current version information to maintain awareness of outdated software, and mapping assets to business and critical functions.
  • Determine the need and functionality of assets that require public internet exposure. [CPG 2.3]

VALIDATE SECURITY CONTROLS

In addition to applying mitigations, CISA, FBI, and MS-ISAC recommend exercising, testing, and validating your organization’s security program against the threat behaviors mapped to the MITRE ATT&CK for Enterprise framework in this advisory. CISA and co-sealers recommend testing your existing security controls inventory to assess how they perform against the ATT&CK techniques described in this advisory.

To get started:

1. Select an ATT&CK technique described in this advisory (see Table 4).
2. Align your security technologies against the selected technique.
3. Test your technologies against the technique.
4. Analyze your detection and prevention technologies’ performance.
5. Repeat the process for all security technologies to obtain a set of comprehensive performance data.
6. Tune your security program—including people, processes, and technologies—based on the data generated by this process.

CISA, FBI, and MS-ISAC recommend continually testing your security program, at scale, in a production environment to ensure optimal performance against the MITRE ATT&CK techniques identified in this advisory.

RESOURCES

UNIX Timestamp Converter

REFERENCES

[1] Telerik: Exploiting .NET JavaScriptSerializer Deserialization (CVE-2019-18935)
[2] ACSC Advisory 2020-004
[3] Bishop Fox CVE-2019-18935: Remote Code Execution via Insecure Deserialization in Telerik UI
[4] Volexity Threat Research: XE Group
[5] GitHub: Proof-of-Concept Exploit for CVE-2019-18935
[6] Microsoft: Configure Logging in IIS
[7] GitHub: CVE-2019-18935

ACKNOWLEDGEMENTS

Google’s Threat Analysis Group (TAG) contributed to this CSA.

Please share your thoughts. We recently updated our anonymous Product Feedback Survey and we’d welcome your feedback.

Source de l’article sur us-cert.gov

SUMMARY

Note: This joint Cybersecurity Advisory (CSA) is part of an ongoing #StopRansomware effort to publish advisories for network defenders that detail various ransomware variants and ransomware threat actors. These #StopRansomware advisories include recently and historically observed tactics, techniques, and procedures (TTPs) and indicators of compromise (IOCs) to help organizations protect against ransomware. Visit stopransomware.gov to see all #StopRansomware advisories and to learn more about other ransomware threats and no-cost resources.

Actions to take today to mitigate cyber threats from ransomware:

• Prioritize remediating known exploited vulnerabilities.
• Train users to recognize and report phishing attempts.
• Enable and enforce multifactor authentication.

The Federal Bureau of Investigation (FBI) and the Cybersecurity and Infrastructure Security Agency (CISA) are releasing this joint CSA to disseminate known Royal ransomware IOCs and TTPs identified through FBI threat response activities as recently as January 2023.

Since approximately September 2022, cyber criminals have compromised U.S. and international organizations with a Royal ransomware variant. FBI and CISA believe this variant, which uses its own custom-made file encryption program, evolved from earlier iterations that used “Zeon” as a loader. After gaining access to victims’ networks, Royal actors disable antivirus software and exfiltrate large amounts of data before ultimately deploying the ransomware and encrypting the systems. Royal actors have made ransom demands ranging from approximately $1 million to $11 million USD in Bitcoin. In observed incidents, Royal actors do not include ransom amounts and payment instructions as part of the initial ransom note. Instead, the note, which appears after encryption, requires victims to directly interact with the threat actor via a .onion URL (reachable through the Tor browser). Royal actors have targeted numerous critical infrastructure sectors including, but not limited to, Manufacturing, Communications, Healthcare and Public Healthcare (HPH), and Education.

FBI and CISA encourage organizations to implement the recommendations in the Mitigations section of this CSA to reduce the likelihood and impact of ransomware incidents.

Download the PDF version of this report:

For a downloadable copy of IOCs, see

TECHNICAL DETAILS

Note: This advisory uses the MITRE ATT&CK® for Enterprise framework, version 12. See MITRE ATT&CK for Enterprise for all referenced tactics and techniques.

Royal ransomware uses a unique partial encryption approach that allows the threat actor to choose a specific percentage of data in a file to encrypt. This approach allows the actor to lower the encryption percentage for larger files, which helps evade detection.[1] In addition to encrypting files, Royal actors also engage in double extortion tactics in which they threaten to publicly release the encrypted data if the victim does not pay the ransom.

Initial Access

Royal actors gain initial access to victim networks in a number of ways including: 

• Phishing. According to third-party reporting, Royal actors most commonly (in 66.7% of incidents) gain initial access to victim networks via successful phishing emails [T1566].
  • According to open-source reporting, victims have unknowingly installed malware that delivers Royal ransomware after receiving phishing emails containing malicious PDF documents [T1566.001], and malvertising [T1566.002].[2]
• Remote Desktop Protocol (RDP). The second most common vector Royal actors use (in 13.3% of incidents) for initial access is RDP compromise.  
• Public-facing applications. FBI has also observed Royal actors gain initial access through exploiting public-facing applications [T1190]. 
• Brokers. Reports from trusted third-party sources indicate that Royal actors may leverage brokers to gain initial access and source traffic by harvesting virtual private network (VPN) credentials from stealer logs. 

Command and Control

Once Royal actors gain access to the network, they communicate with command and control (C2) infrastructure and download multiple tools [T1105]. Legitimate Windows software is repurposed by Royal operators to strengthen their foothold in the victim’s network. Ransomware operators often use open-source projects to aid their intrusion activities; Royal operators have recently been observed using Chisel, a tunneling tool transported over HTTP and secured via SSH [T1572], to communicate with their C2 infrastructure. FBI has observed multiple Qakbot C2s used in Royal ransomware attacks, but has not yet determined if Royal ransomware exclusively uses Qakbot C2s.

Lateral Movement and Persistence

Royal actors often use RDP to move laterally across the network [T1021.001]. Microsoft Sysinternals tool PsExec has also been used to aid lateral movement. FBI has observed Royal actors using remote monitoring and management (RMM) software, such as AnyDesk, LogMeIn, and Atera, for persistence in the victim’s network [T1133]. In some instances, the actors moved laterally to the domain controller. In one confirmed case, the actors used a legitimate admin account to remotely log on to the domain controller [T1078]. Once on the domain controller, the threat actor deactivated antivirus protocols [T1562.001] by modifying Group Policy Objects [T1484.001].

Exfiltration

Royal actors exfiltrate data from victim networks by repurposing legitimate cyber pentesting tools, such as Cobalt Strike, and malware tools and derivatives, such as Ursnif/Gozi, for data aggregation and exfiltration. According to third-party reporting, Royal actors’ first hop in exfiltration and other operations is usually a U.S. IP address.

Note: In reference to Cobalt Strike and other tools mentioned above, a tool repository used by Royal was identified at IP: 94.232.41[.]105 in December 2022.

Encryption

Before starting the encryption process, Royal actors: 

• Use Windows Restart Manager to determine whether targeted files are currently in use or blocked by other applications [T1486].[1] 
• Use Windows Volume Shadow Copy service (vssadmin.exe) to delete shadow copies to prevent system recovery.[1]  

FBI has found numerous batch (.bat) files on impacted systems which are typically transferred as an encrypted 7zip file. Batch files create a new admin user [T1078.002], force a group policy update, set pertinent registry keys to auto-extract [T1119] and execute the ransomware, monitor the encryption process, and delete files upon completion—including Application, System, and Security event logs [T1070.001].

Malicious files have been found in victim networks in the following directories:

• C:Temp  
• C:UsersAppDataRoaming  
• C:Users 
• C:ProgramData

Indicators of Compromise (IOC)

See table 1 and 2 for Royal ransomware IOCs that FBI obtained during threat response activities as of January 2023. Note: Some of the observed IP addresses are several months old. FBI and CISA recommend vetting or investigating these IP addresses prior to taking forward-looking action, such as blocking.

Table 1: Royal Ransomware Associated Files, Hashes, and IP addresses as of January 2023

IOC	Description
.royal	Encrypted file extension
README.TXT	Ransom note
Malicious IP	Last Activity
102.157.44[.]105	November 2022
105.158.118[.]241	November 2022
105.69.155[.]85	November 2022
113.169.187[.]159	November 2022
134.35.9[.]209	November 2022
139.195.43[.]166	November 2022
139.60.161[.]213	November 2022
148.213.109[.]165	November 2022
163.182.177[.]80	November 2022
181.141.3[.]126	November 2022
181.164.194[.]228	November 2022
185.143.223[.]69	November 2022
186.64.67[.]6	November 2022
186.86.212[.]138	November 2022
190.193.180[.]228	November 2022
196.70.77[.]11	November 2022
197.11.134[.]255	November 2022
197.158.89[.]85	November 2022
197.204.247[.]7	November 2022
197.207.181[.]147	November 2022
197.207.218[.]27	November 2022
197.94.67[.]207	November 2022
23.111.114[.]52	November 2022
41.100.55[.]97	November 2022
41.107.77[.]67	November 2022
41.109.11[.]80	November 2022
41.251.121[.]35	November 2022
41.97.65[.]51	November 2022
42.189.12[.]36	November 2022
45.227.251[.]167	November 2022
5.44.42[.]20	November 2022
61.166.221[.]46	November 2022
68.83.169[.]91	November 2022
81.184.181[.]215	November 2022
82.12.196[.]197	November 2022
98.143.70[.]147	November 2022
140.82.48[.]158	December 2022
147.135.36[.]162	December 2022
147.135.11[.]223	December 2022
152.89.247[.]50	December 2022
179.43.167[.]10	December 2022
185.7.214[.]218	December 2022
193.149.176[.]157	December 2022
193.235.146[.]104	December 2022
209.141.36[.]116	December 2022
45.61.136[.]47	December 2022
45.8.158[.]104	December 2022
5.181.234[.]58	December 2022
5.188.86[.]195	December 2022
77.73.133[.]84	December 2022
89.108.65[.]136	December 2022
94.232.41[.]105	December 2022
47.87.229[.]39	January 2023
Malicious Domain	Last Observed
ciborkumari[.]xyz	October 2022
sombrat[.]com	October 2022
gororama[.]com	November 2022
softeruplive[.]com	November 2022
altocloudzone[.]live	December 2022
ciborkumari[.]xyz	December 2022
myappearinc[.]com	December 2022
parkerpublic[.]com	December 2022
pastebin.mozilla[.]org/Z54Vudf9/raw	December 2022
tumbleproperty[.]com	December 2022
myappearinc[.]com/acquire/draft/c7lh0s5jv	January 2023

Table 2: Tools used by Royal operators

Tool	SHA256
AV tamper	8A983042278BC5897DBCDD54D1D7E3143F8B7EAD553B5A4713E30DEFFDA16375
TCP/UDP Tunnel over HTTP (Chisel)	8a99353662ccae117d2bb22efd8c43d7169060450be413af763e8ad7522d2451
Ursnif/Gozi	be030e685536eb38ba1fec1c90e90a4165f6641c8dc39291db1d23f4ee9fa0b1
Exfil	B8C4AEC31C134ADBDBE8AAD65D2BCB21CFE62D299696A23ADD9AA1DE082C6E20
Remote Access (AnyDesk)	4a9dde3979c2343c024c6eeeddff7639be301826dd637c006074e04a1e4e9fe7
PowerShell Toolkit Downloader	4cd00234b18e04dcd745cc81bb928c8451f6601affb5fa45f20bb11bfb5383ce
PsExec (Microsoft Sysinternals)	08c6e20b1785d4ec4e3f9956931d992377963580b4b2c6579fd9930e08882b1c
Keep Host Unlocked (Don’t Sleep)	f8cff7082a936912baf2124d42ed82403c75c87cb160553a7df862f8d81809ee
Ransomware Executable	d47d4b52e75e8cf3b11ea171163a66c06d1792227c1cf7ca49d7df60804a1681
Windows Command Line (NirCmd)	216047C048BF1DCBF031CF24BD5E0F263994A5DF60B23089E393033D17257CB5
System Management (NSudo)	19896A23D7B054625C2F6B1EE1551A0DA68AD25CDDBB24510A3B74578418E618
Batch Scripts
Filename	Hash Value
2.bat	585b05b290d241a249af93b1896a9474128da969
3.bat	41a79f83f8b00ac7a9dd06e1e225d64d95d29b1d
4.bat	a84ed0f3c46b01d66510ccc9b1fc1e07af005c60
8.bat	c96154690f60a8e1f2271242e458029014ffe30a
kl.bat	65dc04f3f75deb3b287cca3138d9d0ec36b8bea0
gp.bat	82f1f72f4b1bfd7cc8afbe6d170686b1066049bc7e5863b51aa15ccc5c841f58
r.bat	74d81ef0be02899a177d7ff6374d699b634c70275b3292dbc67e577b5f6a3f3c
runanddelete.bat	342B398647073159DFA8A7D36510171F731B760089A546E96FBB8A292791EFEE

MITRE ATT&CK TECHNIQUES

See table 3 for all referenced threat actor tactics and techniques included in this advisory.

Table 3: Royal Actors ATT&CK Techniques for Enterprise

Initial Access
Technique Title	ID	Use
Exploit Public Facing Application	T1190	The actors gain initial access through public-facing applications.
Phishing: Spear phishing Attachment	T1566.001	The actors gain initial access through malicious PDF attachments sent via email.
Phishing: Spearphishing Link	T1566.002	The actors gain initial access using malvertising links via emails and public-facing sites.
External Remote Services	T1133	The actors gain initial access through a variety of RMM software.
Command and Control
Technique Title	ID	Use
Ingress Tool Transfer	T1105	The actors used C2 infrastructure to download multiple tools.
Protocol Tunneling	T1572	The actors used an encrypted SSH tunnel to communicate within C2 infrastructure.
Privilege Escalation
Technique Title	ID	Use
Valid Accounts: Domain Accounts	T1078.002	The actors used encrypted files to create new admin user accounts.
Defense Evasion
Technique Title	ID	Use
Impair Defenses: Disable or Modify Tools	T1562.001	The actors deactivated antivirus protocols.
Domain Policy Modification: Group Policy Modification	T1484.001	The actors modified Group Policy Objects to subvert antivirus protocols.
Indicator Removal: Clear Windows Event Logs	T1070.001	The actors deleted shadow files and system and security logs after exfiltration.
Remote Desktop Protocol	T1021.001	The actors used valid accounts to move laterally through the domain controller using RDP.
Automated Collection	T1119	The actors used registry keys to auto-extract and collect files.
Impact
Technique Title	ID	Use
Data Encrypted for Impact	T1486	The actors encrypted data to determine which files were being used or blocked by other applications.

MITIGATIONS

FBI and CISA recommend network defenders apply the following mitigations to limit potential adversarial use of common system and network discovery techniques and to reduce the risk of compromise by Royal ransomware. These mitigations follow CISA’s Cybersecurity Performance Goals (CPGs), which provide a minimum set of practices and protections that are informed by the most common and impactful threats, tactics, techniques, and procedures, and which yield goals that all organizations across critical infrastructure sectors should implement:

• Implement a recovery plan to maintain and retain multiple copies of sensitive or proprietary data and servers [CPG 7.3] in a physically separate, segmented, and secure location (i.e., hard drive, storage device, the cloud).
• Require all accounts with password logins (e.g., service account, admin accounts, and domain admin accounts) to comply with National Institute for Standards and Technology (NIST) standards for developing and managing password policies [CPG 3.4].
  • Use longer passwords consisting of at least 8 characters and no more than 64 characters in length [CPG 1.4].
  • Store passwords in hashed format using industry-recognized password managers.
  • Add password user “salts” to shared login credentials.
  • Avoid reusing passwords.
  • Implement multiple failed login attempt account lockouts [CPG 1.1].
  • Disable password hints.
  • Refrain from requiring password changes more frequently than once per year. Note: NIST guidance suggests favoring longer passwords instead of requiring regular and frequent password resets. Frequent password resets are more likely to result in users developing password patterns cyber criminals can easily decipher. 
  • Require administrator credentials to install software.
• Require multifactor authentication [CPG 1.3] for all services to the extent possible, particularly for webmail, virtual private networks, and accounts that access critical systems. 
• Keep all operating systems, software, and firmware up to date. Timely patching is one of the most efficient and cost-effective steps an organization can take to minimize its exposure to cybersecurity threats. 
• Segment networks [CPG 8.1]. Network segmentation can help prevent the spread of ransomware by controlling traffic flows between—and access to—various subnetworks and by restricting adversary lateral movement. 
• Identify, detect, and investigate abnormal activity and potential traversal of the indicated ransomware with a networking monitoring tool. To aid in detecting ransomware, implement a tool that logs and reports all network traffic [CPG 5.1], including lateral movement activity on a network. Endpoint detection and response (EDR) tools are useful for detecting lateral connections as they have insight into common and uncommon network connections for each host. 
• Install, regularly update, and enable real time detection for antivirus software on all hosts.
• Review domain controllers, servers, workstations, and active directories for new and/or unrecognized accounts.
• Audit user accounts with administrative privileges and configure access controls according to the principle of least privilege [CPG 1.5].
• Disable unused ports.
• Consider adding an email banner to emails [CPG 8.3] received from outside your organization.
• Implement time-based access for accounts set at the admin level and higher. For example, the Just-in-Time (JIT) access method provisions privileged access when needed and can support enforcement of the principle of least privilege (as well as the Zero Trust model). This is a process where a network-wide policy is set in place to automatically disable admin accounts at the Active Directory level when the account is not in direct need. Individual users may submit their requests through an automated process that grants them access to a specified system for a set timeframe when they need to support the completion of a certain task. 
• Disable command-line and scripting activities and permissions. Privilege escalation and lateral movement often depend on software utilities running from the command line. If threat actors are not able to run these tools, they will have difficulty escalating privileges and/or moving laterally. 
• Maintain offline backups of data, and regularly maintain backup and restoration [CPG 7.3]. By instituting this practice, the organization ensures they will not be severely interrupted, and/or only have irretrievable data. 
• Ensure all backup data is encrypted, immutable (i.e., cannot be altered or deleted), and covers the entire organization’s data infrastructure [CPG 3.3].

RESOURCES

• Stopransomware.gov is a whole-of-government approach that gives one central location for ransomware resources and alerts.
• Resource to mitigate a ransomware attack: CISA-Multi-State Information Sharing and Analysis Center (MS-ISAC) Joint Ransomware Guide.
• No-cost cyber hygiene services: Cyber Hygiene Services and Ransomware Readiness Assessment.

REPORTING

FBI is seeking any information that can be shared, to include boundary logs showing communication to and from foreign IP addresses, a sample ransom note, communications with Royal actors, Bitcoin wallet information, decryptor files, and/or a benign sample of an encrypted file.

Additional details requested include: a targeted company Point of Contact, status and scope of infection, estimated loss, operational impact, transaction IDs, date of infection, date detected, initial attack vector, host and network based indicators.

FBI and CISA do not encourage paying ransom as payment does not guarantee victim files will be recovered. Furthermore, payment may also embolden adversaries to target additional organizations, encourage other criminal actors to engage in the distribution of ransomware, and/or fund illicit activities. Regardless of whether you or your organization have decided to pay the ransom, FBI and CISA urge you to promptly report ransomware incidents to a local FBI Field Office, or CISA at https://www.cisa.gov/report.

DISCLAIMER

The information in this report is being provided “as is” for informational purposes only. CISA and FBI do not endorse any commercial product or service, including any subjects of analysis. Any reference to specific commercial products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply endorsement, recommendation, or favoring by CISA or the FBI.

REFERENCES

[1] Royal Rumble: Analysis of Royal Ransomware (cybereason.com)
[2] DEV-0569 finds new ways to deliver Royal ransomware, various payloads – Microsoft Security Blog
[3] 2023-01: ACSC Ransomware Profile – Royal | Cyber.gov.au

ACKNOWLEDGEMENTS

Recorded Future, Coveware, Digital Asset Redemption, Q6, and RedSense contributed to this CSA.

Please share your thoughts. We recently updated our anonymous Product Feedback Survey and we’d welcome your feedback.

Source de l’article sur us-cert.gov