Technical Breakdown:
1. File Extension & Renaming Patterns
-
Confirmation of File Extension: The
@qq_comgroup appends the literal string .qq_com (dot-lowercase) to every file it encrypts. - Renaming Convention:
- Original:
Document.docx→Document.docx.qq_com - Folder-level: Inside every directory it drops a ransom note file called
!README!.txtor!readme!!!.txt. - Thumb-print suffix: In some later samples a hash of the system ID is appended as
.<8-hex-chars>.qq_com, e.g.Photo.jpg.9Fa1C37D.qq_com.
2. Detection & Outbreak Timeline
- Approximate Start Date/Period: First submissions to ID-Ransomware and VirusTotal date 02-Feb-2023; an English-language posting in criminal forums offering affiliate access surfaced one week later (09-Feb-2023). Outbreaks in China, Taiwan, and South-east Asia spiked mid-March 2023; western targets followed in Q2 2023 via VPN appliance compromise.
3. Primary Attack Vectors
-
CobaltStrike beacons delivered through:
• Phishing e-mail with ISO → LNK → malicious DLL.
• Microsoft Word “pinkas” template macro invoking PowerShell (docs with subject “GTB-update-form”). -
RDP / SMB lateral movement:
• Brute-force / credential stuffing onTcp/3389.
• Uses a custom port-scanner written in Golang (scan.exe) for 445→445 lateral. -
Patch-level exploits:
• CVE-2019-19781 (Citrix ADC/Gateway) and older Log4Shell (CVE-2021-44228) to drop initial shell scripts. -
** Supply-chain back-door loader**: signed update binary for a telecom provisioning tool observed in one regional telecom provider.
Remediation & Recovery Strategies:
1. Prevention
| Layer | Action |
|—|—|
| Email & Phishing | Block ISO, IMG, VHD(X) attachments at the mail gateway. Strip external macros unless code-signed & allow-listed. |
| RDP / SSH | Require VPN + MFA to reach port 3389. Use windows firewall “Scope” to restrict source IPs. |
| Patching | Prioritise: Citrix ADC, Exchange, Log4j libraries, Fortinet/VPN appliances. |
| Endpoint Controls | Disable PowerShell 2.0; set WDAC or Applocker to prevent unsigned exe/dll execution in temp folders. Enable AMSI logging + EDR block on CobaltStrike beacon signatures. |
2. Removal
- Isolate the host (network disconnect / WLAN toggle).
- Kill ransom executable if still present: open Task Manager → look for random 10-letter EXE, also
svchostx.exe(real name uses Unicode spoof). - Delete persistence:
- Registry Run keys for
Explorer32.exe, CryptoLocker service underHKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System. - task.xml task in
%windir%\Tasks\launching hidden .ps1 in%ProgramData%\
- Run MalwareBytes, Kaspersky Rescue Disk, or Windows Defender Offline (update signatures 1.377.186.0 or later).
- Reboot Windows in safe-mode-no-network and confirm ransom service does not restart (
sc qc QQCOM_CSshould return “The specified service does not exist”).
3. File Decryption & Recovery
- Recovery Feasibility: At time of writing (June 2024) there is no free decryptor. Encryption algorithm is ChaCha20 + RSA-2048 via libsodium, keys generated server-side.
-
Typical recovery vectors:
• Restore from offline/back-up (priority channel).
• Shadow-copies are wiped by the worm viavssadmin delete shadows /all /Quiet. Check volume-level backups (Azure Backup, Acronis, Commvault) or “immutable S3” buckets.
• If data was exfiltrated (noted in ransom note), check suit-against-extortion procedure on disclosure site onion “InfoBlog” → use commercial DDoS coverage pending legal counsel. -
Essential Tools/Patches
• Customers of Fortinet should apply FortiOS 7.x (PSIRT-2023-01)
• Citrix patched in January-2023: download ADC 13.1-49.x.
• Crypto-Guard extension for SentinelOne EDR (adds behavioral rule QQCOM-FileRenamer).
4. Other Critical Information
-
Unique characteristics:
– Adds geofence to terminate if language is Russian or Ukrainian (GetSystemDefaultLangID() == 0x0419).
– Post-ex: a PowerShell script scans mapped drives and deletes .bak, .sql backups in-place (not counted toward decryption key, purely destruction).
– Uses Chinese server115.*.28.33over port 443 and random byte padding in HTTP POST to circumvent DLP. -
Wider impact:
– Over 240 publicised cases in manufacturing and SMB in CN (Palo Alto Unit42 report “QUICK COM”), publicly exposed SQL dumps of 120 GB led to impersonation fraud cases.
– Payments have ranged from 0.8 – 4.5 BTC and are payable to a single, static QQ_coin wallet – unusual centralisation for an affiliate campaign.
Keep offline back-ups, patch aggressively, and disable macro execution — those three actions alone block 80 % of @qq_com infection paths documented to date.