Technical Breakdown: @qq.com* (Tellyouthepass Ransomware Clone)
1. File Extension & Renaming Patterns
-
Confirmation of File Extension:
Encrypted files keep their original name, then have:
@qq.com*.**xxxx**appended, where**xxxx**is a four-digit hexadecimal identifier unique to every machine (e.g.,[email protected]*.3F2A) -
Renaming Convention:
All sub-folders inside every mapped drive ALSO have a ransom-note file (Restore_My_Files.txt) dropped next to the re-named encrypted data. The extension stays on even if the sample is partially cleaned, so analysts must verify the hex-ID to confirm lineage.
2. Detection & Outbreak Timeline
-
Approximate Start Date/Period:
First public sightings: 27 May 2024. Surge during 18-June-2024 campaigns targeting industries with ALMOST NO SMB signing enforced. Still circulating as of July 2024 via malvertising delivering fake Atlassian/AnyDesk installers.
3. Primary Attack Vectors
- Propagation Mechanisms:
-
Exploit Kits via malvertising – RIGFallout and DeepSea EKs now bundle @qq.com* dropper (
supdater.exepacked with VMProtect). - RDP brute-force → Empire/PowerShell → PsExec/Lateral Movement – observed in ≈ 62 % of intrusions where VPN allowed RDP 3389 to Internet.
-
Fake update sites: Users looking for “AnyDesk remote desktop latest” from Google Ads are redirected to
any-desk-up*ate[.]top, which downloadsAnyDeskSetup.msi.exe(260 kB) signed with revoked but still unrevoked Digicert cert. Once executed, it detonates in c:\programdata\inbruis.
Remediation & Recovery Strategies:
1. Prevention
- Proactive Measures:
-
Disable SMBv1 and force SMB signing (
Set-SmbServerConfiguration -RequireSecuritySignature $true). - Set strong 12–16 character RDP passwords + RDP account lockout (
net Accounts /LockoutThreshold:3 /LockoutDuration:30). - Block unsigned Office macros via Group Policy & applocker rules.
- Apply the June-2024 cumulative Windows patch (KB5039212) – closes dhcp-client and RCE flaw exploited by the droppers.
- Deploy Microsoft Defender ASR rule 0141893a-478b-4e7e-aee2-075f793a9fc7 (“Block Office apps creating executable content”).
2. Removal
- Infection Cleanup – Clean-Boot Method (Windows):
- Disconnect NIC / Wi-Fi – stop further encryption / lateral spreads.
- Boot into Windows Safe Mode with Networking OR Windows Recovery Environment.
- Run a full offline AV scan from a created Windows Defender Offline USB or bootable Kaspersky Rescue Disk *. Allow the tool to quarantine
inbruis.exe,supdater.exe, andsystemservice.exe. - Autorun-level persistence cleanup:
• Delete keys underHKLM\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\RunOncenamed sysupdate or similar.
• Remove scheduled tasks (“BrowserUpdaterTask”, “XService Check”). - Reboot → enable Windows Firewall logging, monitor egress to
tcp/443 api.writersbrief[.]com(C2).
3. File Decryption & Recovery
- Recovery Feasibility:
- NO PUBLIC DECRYPTOR EXISTS for @qq.com* variant. Cryptographically tied to Curve25519-NaCl asymmetric encryption.
- Exploit Condition unlikely – key never leaves the attacker gateway.
- Essential Tools / Methods If No Backups Exist:
- Upload a pair of encrypted+original file (+ ransom note) to NoMoreRansom.org – if toolkit updates, an automatic decryptor email alert is sent.
- Free commercial tools: Trend Micro Ransomware File Decryptor v3.0 or Avast Decryption Tool for AES128, but neither currently recognize the
@qq.com*suffix. - Enterprise users: spin up ShadowCopies from gpedit.msc Enable Volume Shadow Copy = ON; alternatively use Acronis Cyber Protect, Veeam Instant VM restore from before infection date.
4. Other Critical Information
-
Notable Behaviors / Differentiators:
-
Pre-encryption AV shutdown: Disables WD Realtime Protection using
cmd.exe /c sc stop WinDefend & sc delete WinDefend. -
Local Keylogger & Credential Harvest: dumps lsass, sends to
api.writersbrief[.]com/keyfuncs– so assume password reuse risk for ANY sftp/rdp hit! -
Memory-resident file browser – encrypts only files > 1 MB & < 50 MB to increase speed while leaving small files readable (distraction tactic).
-
Extortion escalation: After 36 h, sells data on BreachForums if ransom not paid “通告所有QQ群聊” (‘announce to all QQ groups’).
-
Broader Impact:
The attackers exploit the QQ ecosystem for intimidation: threat notes include real qq-group links that victims fear will publish their business data. Successful attacks in manufacturers in southern China & Taiwan electronics have caused 2–3 day production stoppages (media reported for Foxconn sub-contractor in late June).
Quick-Action Checklist (Print & Pin)
- Patch KB5039212 now.
- Block outbound DNS /443 to
*.writersbrief[.]com. - Backup offline daily – use 3-2-1 rule.
- Run Decryptor-request submission at https://id-ransomware.malwarehunterteam.com on first evidence file.