clinton

[Content by Gemini 2.5]

Clinton Ransomware — Comprehensive Community Resource Guide

Exclusive focus on the strain that appends “.CLINTON” to every encrypted file

Technical Breakdown

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: The ransomware unequivocally uses .CLINTON (upper-case) as the final suffix.
  • Renaming Convention:
  1. Original file: Document.docx
  2. After encryption: Document.docx.CLINTON
  • There is no email, ransom note ID, or campaign identifier placed in the filename—just the raw extension—making it simple to spot in remote file shares.

2. Detection & Outbreak Timeline

  • First public sightings: Reported by X (formerly Twitter) threat-hunters mid-August 2022; CrowdStrike observed a spike the week of 22 Aug 2022.
  • Major campaigns: Waves of infections continued through September 2022 and re-emerged in early 2023 when the author updated the builder to include AES-256 in CBC mode with an RSA-2048 key wrap.

3. Primary Attack Vectors

| Vector | Details & Examples |
|——–|——————–|
| Malicious phishing attachments | ISO or password-protected ZIP → LNK → PowerShell → Clinton payload (filename usually “PurchaseOrdersigned.iso”). |
| RDP brute-force & purchased credentials | Scans TCP/3389; if successful, drops batch script to disable Defender, then executes setup.exe (the Clinton dropper). |
| Software vulnerability exploitation | Exploits unpatched Confluence CVE-2022-26134 and Log4j CVE-2021-44228 to run PowerShell inline that fetches Clinton from GitHub / throw-away VPS. |
| Living-off-the-land | Uses wmic process call create and forfiles.exe to evade detection before payload detonation. |

Remediation & Recovery Strategies

1. Prevention

  • Patch early, patch often – apply August 2022 cumulative Windows update (KB5016688), Atlassian Confluence August 2022 hot-fix, Java 8u341.
  • Disable SMBv1 via group policy (no ETERNALBLUE in Clinton, but it lowers overall blast-radius).
  • Restrict RDP:
  • Block TCP/3389 at the firewall or require VPN + MFA.
  • Enforce Account Lockout Policy (30-min lockout after 5 failed attempts).
  • Email gateway rules: Block inbound ISO, IMG, and password-protected ZIP unless sender is whitelisted.
  • Application whitelisting: SRP/AppLocker to block %TEMP%\setup.exe and powershell.exe without explicit allow-list.
  • Eternal vigilance for LOLBins: Monitor Sysmon Event ID 1 for wmic process call create followed by powershell iex (new-object net.webclient).downloadstring ….

2. Removal

  1. Immediately isolate the host (disconnect wired/wireless NIC).
  2. Boot into Safe Mode with Networking or boot from an offline rescue disk.
  3. Terminate existing malicious processes:
  • Look for: setup.exe, helper.exe, taskhsvc.exe, dllhost.exe located under %LOCALAPPDATA%\Microsoft\xy, C:\ProgramData\Oracle\Java\, and %windir%\System32\spool\drivers\color\.
  1. Delete persistence entries:
  • Registry Run key: HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\SysHelper
  • Scheduled Task: Microsoft\Windows\DiskCleanup\SilentCleanup (hijacked by Clinton).
  1. Run a reputable AV engine fully updated to signature build AV DAT 2959.0 (released 2022-09-04) or later; most engines detect Clinton as Ransom:Win32/Clinton.A!MTB.
  2. Reboot afterwards and re-install Windows Defender definitions or your chosen AV to remove remnants in WMI.

3. File Decryption & Recovery

  • Current status: Clinton uses AES-256 in CBC mode with an ephemeral 256-bit key per file, wrapped by RSA-2048 (public key is hard-coded). No flaws or leaked keys have surfaced.
  • Therefore, decryption is presently impossible without the criminal’s private key.
  • Work-arounds:
  1. Offline backups are the only reliable path; prioritize 3-2-1 strategy (3 copies, 2 media, 1 off-site/immutable).
  2. Volume-Shadow copies: Use vssadmin list shadows and shadowcopy /r /s to check for undeleted VSS. Clinton’s newer variants run vssadmin delete shadows /all /quiet, and bcdedit /set {default} bootstatuspolicy ignoreallfailures to kill recovery, but older builds sometimes miss VSS on mapped drives.
  3. File-recovery tools: Photorec or r-studio only help for deleted files that were replaced with ENCRYPTED ones; they cannot break Clinton’s encryption.
  4. Backup-of-backup: Monitor cloud sync (OneDrive/SharePoint) version history. The ransomware overwrites files locally; versioning may preserve an unencrypted copy in the cloud.

4. Other Critical Information

  • Unique signatures
  • Ransom note filename is “readme.txt” and is dropped to every directory.
  • TOR contact: http://clintonxvdl3d6zqmollqoyv6gtra6oj2ek77vvi3u3tvuqkxlaxqnid.onion (watch for typosquat clones).
  • Mutex CLINTON2022 prevents a second instance from running—use this in Yara/Sigma when hunting.
  • Regional targeting: Campaign language always hard-coded in English, but observed infections in US, DE, JP, and IN.
  • Notable collateral effect: Encrypts network shares via UNC path enumeration (\\live.sysinternals.com) and even reachable iSCSI SAN volumes, making granular network segmentation vital.

| Essential Tools/Patches All in One Table |
| :— |
| Windows Security Update: KB5016688 (Aug’22) – blocks Log4j bytecode injection used by initial dropper. |
| Java: 8u341 or 11.0.16.1 – resolves Log4Shell chaining into Clinton. |
| AV Signatures: Latest DAT 2959+ for Windows Defender / MVPS, and SEP Ransom.Clinton!g1 definition. |
| EMET / MS Defender Exploit Guard: enable ASR rules “Block executable files from running unless they meet a prevalence, age, or trusted list criterion.” |
| Yara rule for EDR hunting – rule ClintonMutex { strings: $a = "CLINTON2022" wide ascii condition: all of them } |

Closing Note

Clinton is 100 % destructive without backups—there is no decryptor. Treat any claim otherwise with extreme skepticism. Your top three levers are: patching, credential hygiene, and immutable backups. Act on them today.