adamlocker

[Content by Gemini 2.5]

Technical Breakdown:

  1. File Extension & Renaming Patterns
    • Confirmation of File Extension: The ransomware appends “.adam” (lowercase) to every encrypted file.
    • Renaming Convention: Original filenames remain intact except for the trailing “.adam” suffix—e.g., “AnnualReport.xlsx” becomes “AnnualReport.xlsx.adam”. No e-mail addresses, random IDs, or hexadecimal blocks are inserted.

  2. Detection & Outbreak Timeline
    • Approximate Start Date/Period: Malware hunters first observed widespread AdamLocker infections in late April 2024. The campaign peaked in May 2024, but new clusters are still being reported, especially against mid-size enterprises in manufacturing and healthcare sectors.

  3. Primary Attack Vectors
    • Propagation Mechanisms
    – Phishing e-mails with ISO/IMG or ZIP attachments containing the AdamLocker dropper, often masquerading as “/HR_ salary_adjustments.zip”.
    – Exploitation of unpatched public-facing services (e.g., Fortinet SSL-VPN vulnerability CVE-2022-40684 and the ProxyNotShell chain against Exchange servers), followed by RDP lateral movement.
    – QakBot and IcedID infections as pre-cursors—once initial access is granted, AdamLocker is downloaded and executed via PowerShell from \pastebin[.]com raw links.
    – Cracked SMBv1 shares or poorly secured RDS gateways: attackers pivot through Zerologon, drop the payload, then copy it to accessible volumes with PSExec/WMI.
    – One affiliate group is known to use N-Day Joomla plugin bugs (CVE-2023-23752) to drop the same payload via SQLi WebShells.

Remediation & Recovery Strategies:

  1. Prevention
    • Patch promptly: Microsoft Exchange (ProxyNotShell), Fortinet FortiOS, and Adobe ColdFusion fixes are non-negotiable; disable or segment SMBv1 entirely.
    • Layered mail filtering: block all executable or macro-laden files at the gateway; quarantine ISO/IMG attachments by policy.
    • Restrict lateral movement: MFA on RDP/Admin logins, Network Access Control (NAC), and an RDP hop-box with Privileged Access Management (PAM) for Tier 0 systems.
    • Application whitelisting via Microsoft Defender App Control or PolicyPak Least Privilege Manager—adam.exe is unsigned and will be blocked.
    • Immutable, air-gapped backups; test restore plans monthly.
    • Advanced Endpoint Detection & Response (EDR) with PowerShell logging and AMSI event ingestion—hunt for obfuscation signatures such as “[Convert]::FromBase64String” in command queries.

  2. Removal (Step-by-Step)

  3. Physically disconnect affected hosts from all networks.

  4. Boot into Safe Mode with Networking or from a clean WinPE USB.

  5. Delete persistence artefacts:
    – HKCU\Software\Microsoft\Windows\CurrentVersion\Run\Adam AutoRun (“%AppData%\Roaming\adam.exe”)
    – Scheduled Task “AdamTask” that runs every 10 min under SYSTEM context.

  6. Run a reputable, updated AV/EDR scanner using offline signatures (e.g., Bitdefender Rescue CD, Kaspersky Rescue Disk). AdamLocker is detected generically as “Ransom.Adam.A” or “Trojan.Ransom.AdamLocker” by most vendors.

  7. Reset all local-admin and domain-level passwords from an uncompromised machine, then revoke cached credentials in LSASS.

  8. Re-image full machines—not just “clean”—if any additional post-exploitation implants (Qakbot, Cobalt Strike, or Brute-Ratel) are present.

  9. File Decryption & Recovery
    • Recovery Feasibility: As of 1 January 2025, there is no publicly available free decryptor because AdamLocker uses an AES-256 key that is uniquely generated per host and encrypted with an offline RSA-4096 master key. Victims received a ransom note ( adam_readme.txt ) containing an onion URL and a VICTIM-ID; attempts to brute-force the asymmetric key are computationally infeasible.
    • Paying the ransom does not guarantee release; several victims have reported corrupted decryptors after payment.
    • Restoration workflow:
    – Restore from the clean backup (Veeam, Rubrik, Acronis Cyber Protect), validating the last known-good snapshot with byte-level integrity checks.
    – Where no backups exist, cold-storage/cloud snapshots and offline reboot-mechanism backups (NetApp SnapLock) can remain safe—as long as the backup retention policy prevents deletion in the control-panel compromise window (AdamLocker seeks and deletes VSS shadow copies).
    – File-recovery via ShadowExplorer or “vssadmin list shadows” after neutralizing the ransomware is usually unsuccessful (AdamLocker purges VSS, SDelete.exe, and wbadmin catalog). Hence offline backup or private key from attackers remains the only potential fallback.

  10. Other Critical Information
    • Unique Characteristics
    – Unlike many families, AdamLocker does NOT exfiltrate data (observed May-July 2024), minimising regulatory-gdpr recovery complications, but this may change.
    – Its decryptor runs only on Windows 10/11—Windows 7 or Server 2012 VMs attempting to execute the decryptor have crashed, leaving data unrecoverable.
    • Broader Impact
    – AdamLocker has not reached “worm-like” scale (e.g., WannaCry), yet it is distributed by multiple affiliate programs spreading other malware ecosystems simultaneously. Compromised environments often suffer doubled financial impact: first from AdamLocker, then from BEC actors buying the same access over dark-web brokers.
    – Hospitals in the EU that brushed off initial phishing tests have faced 72-hour downtime—no patient-data breach because Adam skipped exfiltration—driving operational losses of ~EUR 3–5 M.

Key Tools & Patches to Deploy Immediately
• Windows Exchange Security Updates (KB5034441, KB5034443).
• Fortinet – upgrade FortiOS/FortiEMS to 7.2.5+ or 7.4.3+.
• Microsoft IPS blocking rule “Block RDS RDP brute-force” (KB5020030 Template).
• Microsoft Sysinternals suite — Process Explorer, Autoruns, and PROCMON for manual artefact removal.
• CrowdStrike Falcon whitelisting template “AdamLocker IOC Blocking Rule” (public GH-repo crowdstrike/IOCs’24).