Lumma Stealer infection with Sectop RAT (ArechClient2), (Fri, Apr 17th)
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✦ AI Summary· Claude Sonnet
Lumma Stealer infection with Sectop RAT (ArechClient2)
Published: 2026-04-17. Last Updated: 2026-04-17 00:30:27 UTC
by Brad Duncan (Version: 1)
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Introduction
This diary provides indicators from a Lumma Stealer infection that was followed by Sectop RAT (ArechClient2). I searched for cracked versions of popular copyright-protected software, and I downloaded the initial malware after following the results of one such search. This is a common distribution technique for various families of malware, and I often find Lumma Stealer this way.
In this case, the initial malware for Lumma Stealer was delivered as a password-protected 7-zip archive. The extracted malware is an inflated Windows executable (EXE) file at 806 MB. The EXE is padded with null-bytes (0x00), a technical which increases the EXE size while allowing the compressed archive file to be much smaller. The password-protected archive and inflated EXE file are designed to avoid detection.
Images from the infection
Shown above: Example of a page with instructions to download the initial malware file.
Shown above: Traffic from the infection filtered in Wireshark.
Shown above: Sectop RAT persistent on an infected Windows host.
Indicators of Compromise
Example of download link from the site advertising cracked versions of copyright-protected software:
hxxps[:]//incolorand[.]com/how-visual-patch-enhances-ui-consistency-across-releases/?utm_source={CID}&utm_term=Adobe%20Premiere%20Pro%20(2026)%20Full%20v26.0.2%20Espa%C3%B1ol%20[Mega]&utm_content={SUBID1}&utm_medium={SUBID2}
Example of URL for page with the file download instructions:
hxxps[:]//mega-nz.goldeneagletransport[.]com/Adobe_Premiere_Pro_%282026%29_Full_v26.0.2_Espa%C3%B1ol_%5BMega%5D.zip?c=ABUZ4WkRgQUA_YUCAFVTFwASAAAAAACh&s=360721
Example of URL for file download from site above site impersonating MEGA:
hxxps[:]//arch.primedatahost3[.]cfd/auth/media/JvWcFd5vUoYTrImvtWQAASTh/Adobe_Premiere_Pro_(2026)_Full_v26.0.2_Espa%C3%B1ol_%5BMega%5D.zip
Downloaded file:
SHA256 hash: c7489e3bf546c5f2d958ac833cc7dbca4368dfba03a792849bc99c48a6b2a14f
File size: 3,888,051 bytes
File name: adobe_premiere_pro_(2026)_full_v26.0.2_espan?ol_[mega].7z
File type: 7-zip archive data, version 0.4
File description: Password-protected 7-zip archive
Password: 6919
Extracted malware:
SHA256 hash: 4849f76dafbef516df91fecfc23a72afffaf77ade51f805eae5ad552bed88923
File size: 806,127,604 bytes
File name: appFile.exe
File type: PE32 executable (GUI) Intel 80386, for MS Windows
File description: Inflated Windows EXE file for Lumma Stealer, padded with null-bytes
Deflated malware:
SHA256 hash: 353ddce78d58aef2083ca0ac271af93659cf0039b0b29d0d169fc015bd3610bc
File size: 7,114,156 bytes
File type: PE32 executable (GUI) Intel 80386, for MS Windows
File description: Above appFile.exe with most of null-byte padding removed
Any.Run sandbox analysis
Triage sandbox analysis
Lumma Stealer command and control (C2) domains from Triage sandbox analysis:
cankgmr[.]cyou
carytui[.]vu
decrnoj[.]club
genugsq[.]best
longmbx[.]click
mushxhb[.]best
pomflgf[.]vu
strikql[.]shop
ulmudhw[.]shop
Follow-up malware:
SHA256 hash: d9b576eb6827f38e33eda037d2cda4261307511303254a8509eeb28048433b2f
File size: 16,450,560 bytes
File type: PE32+ executable (DLL) (GUI) x86-64, for MS Windows
Retrieved from: hxxps[:]//enotsosun[.]pw/NetGui.dll
Saved to: C:\Users\[username]\AppData\Local\Temp\16XBPQ29ZBG94TYNOA.dll
File description: 64-bit DLL to install and run Sectop RAT (ArechClient2)
Run method: rundll32 [file path],LoadForm
Any.Run sandbox analysis
Triage sandbox analysis
Example of Sectop RAT C2 traffic from an infected Windows host:
hxxp[:]//91.92.241[.]102:9000/wmglb
hxxp[:]//91.92.241[.]102:9000/wbinjget?q=66B553A8B94CE37C16F4EBC863D51FCC
tcp[:]//91.92.241[.]102:443/ - encoded or otherwise encrypted traffic (not HTTPS/TLS)
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Bradley Duncan
brad [at] malware-traffic-analysis.net
Keywords: LummaStealer Lumma SectopRAT ArechClient2
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