*id=*2uj**[email protected]*.lazarus

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As a cybersecurity expert specializing in ransomware, I’ve compiled a detailed resource regarding the ransomware variant identified by the file extension *id=*2uj**[email protected]*.lazarus. This variant is characteristic of the STOP/Djvu ransomware family, which is one of the most prolific and continuously evolving ransomware operations. Understanding its patterns is key to effective defense and recovery.

Technical Breakdown:

1. File Extension & Renaming Patterns

  • Confirmation of File Extension:
    The exact file extension used by this ransomware variant is:
    .id=<victim_ID>.<email_address>.lazarus
    For the specific variant you mentioned, this resolves to:
    [email protected]

  • Renaming Convention:
    The ransomware encrypts files and then appends this complex extension to the original filename. The pattern includes a unique victim ID and an email address provided by the attackers for contact, followed by the specific variant’s suffix (.lazarus in this case).

    Example:

    In addition to renaming, the ransomware also drops a ransom note, typically named _readme.txt, in every folder containing encrypted files.

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period:
    The STOP/Djvu ransomware family has been active since late 2017/early 2018 and continuously releases new variants with different file extensions. The .lazarus variant emerged as part of this ongoing campaign, likely appearing in late 2023 or early 2024, following a long line of previous STOP/Djvu iterations. These variants are typically detected shortly after their initial deployment as security researchers track the evolving naming conventions.

3. Primary Attack Vectors

Like other STOP/Djvu variants, the .lazarus ransomware primarily relies on social engineering and deceptive distribution methods:

  • Software Cracks/Keygens/Pirated Software: This is the most prevalent infection vector. Users download compromised software installers, key generators, or cracks from unofficial websites (e.g., torrent sites, warez forums). The ransomware is often bundled discreetly within these seemingly legitimate files.
  • Malicious Bundled Software (Freeware/Shareware): Free software downloads from less reputable sources can include adware, potentially unwanted programs (PUPs), and in some cases, ransomware as a hidden component during installation.
  • Fake Software Updates: Pop-up windows or websites prompting users to “update” critical software (like Flash Player, web browsers, or media players) often deliver malware instead of legitimate updates.
  • Malvertising: Malicious advertisements on legitimate websites can redirect users to infected landing pages or trigger drive-by downloads.
  • Phishing Campaigns (Less Common for Djvu, but possible): While less common than software bundling, email attachments (e.g., seemingly legitimate invoices, shipping notifications, or resumes containing malicious macros) or links to compromised websites can also be used.
  • Remote Desktop Protocol (RDP) Exploits: While not a primary method for STOP/Djvu (more common for enterprise-level ransomware), poorly secured RDP endpoints can theoretically be brute-forced or exploited to gain initial access, though this is less typical for this family’s broad distribution strategy.

Remediation & Recovery Strategies:

1. Prevention

Proactive measures are the most effective defense against .lazarus and similar ransomware:

  • Regular Data Backups: Implement a robust 3-2-1 backup strategy (3 copies of data, 2 different media types, 1 off-site). Ensure backups are isolated from the network to prevent encryption.
  • Reputable Antivirus/Endpoint Detection and Response (EDR): Install and maintain a high-quality antivirus or EDR solution on all endpoints and servers. Keep definitions up-to-date and enable real-time protection.
  • Software Updates & Patch Management: Keep your operating system, web browsers, and all installed software (including third-party applications) fully updated with the latest security patches. Many ransomware attacks exploit known vulnerabilities.
  • Strong Password Policies & MFA: Use strong, unique passwords for all accounts. Enable Multi-Factor Authentication (MFA) wherever possible, especially for critical services and remote access.
  • User Education: Train users about the dangers of downloading pirated software, clicking suspicious links, opening unexpected email attachments, and the importance of verifying software sources.
  • Firewall & Network Segmentation: Configure firewalls to block unauthorized traffic. Segment your network to limit the lateral movement of ransomware in case of an infection.
  • Disable Unnecessary Services: Disable services like RDP if not strictly required, or secure them with strong passwords, MFA, and IP whitelisting if they are.
  • Email Security: Implement email filtering solutions to detect and block malicious attachments and phishing attempts.

2. Removal

If infected, follow these steps to clean up *id=*2uj**[email protected]*.lazarus:

  1. Isolate the Infected System: Immediately disconnect the infected computer from the internet and any local networks (unplug Ethernet cable, disable Wi-Fi). This prevents the ransomware from spreading further or communicating with command-and-control servers.
  2. Identify the Infection Source: Use Task Manager or a process explorer tool to look for suspicious processes. Examine recently downloaded files, especially those related to cracked software or suspicious installers.
  3. Boot into Safe Mode: If possible, boot the computer into Safe Mode with Networking. This can prevent the ransomware from fully executing or interfering with removal tools.
  4. Full System Scan: Perform a comprehensive scan using a reputable and updated antivirus/anti-malware program (e.g., Malwarebytes, ESET, Bitdefender, Windows Defender). Ensure the software has the latest definitions. Allow the scanner to quarantine or remove all detected threats.
  5. Check Startup Entries: Use msconfig (System Configuration) on Windows or Task Manager’s Startup tab to review and disable any suspicious entries that could re-launch the ransomware upon reboot.
  6. Delete Malicious Files: Manually delete any identified ransomware executables or associated files that the antivirus might have missed. Be cautious not to delete legitimate system files.
  7. Remove Ransom Note: Delete the _readme.txt files from all folders after the system is clean.
  8. Change All Passwords: Once the system is confirmed clean, change all passwords for accounts accessed from the infected machine (email, banking, social media, etc.), especially if you suspect credentials might have been compromised.

3. File Decryption & Recovery

  • Recovery Feasibility:
    For STOP/Djvu variants like .lazarus, decryption feasibility largely depends on the encryption key type used:

    • Offline Keys: If the ransomware encrypts files using an “offline” key (a key hardcoded into the ransomware that doesn’t require communication with the attacker’s server), then decryption is possible with a universal decryptor tool.
    • Online Keys: If the ransomware encrypts files using an “online” key (a unique key generated for each victim and stored on the attacker’s server), decryption is extremely difficult, if not impossible, without the specific private key from the attackers. New STOP/Djvu variants, including .lazarus, predominantly use online keys.

    Current Status: As of now, for most recent STOP/Djvu variants (including .lazarus), files encrypted with “online” keys cannot be decrypted for free without the attackers’ cooperation or a major key leak. The Emsisoft Decryptor for STOP/Djvu can check if your files were encrypted with an “offline” key and attempt decryption, but success for recent variants is low.

    Recommendation: Do NOT pay the ransom. There’s no guarantee you’ll receive the decryption key, and it fuels future attacks.

  • Essential Tools/Patches:

    • Emsisoft Decryptor for STOP/Djvu: This is the primary tool to attempt decryption. Download it from Emsisoft’s official website. It’s crucial to understand it only works for files encrypted with an “offline” key.
    • Reputable Anti-Malware Software: (e.g., Malwarebytes, ESET, Bitdefender) for system cleanup.
    • Data Recovery Software: In some rare cases, data recovery tools like PhotoRec or Recuva might be able to recover some unencrypted portions of files, especially if the ransomware didn’t securely overwrite the original data. This is often a long shot.
    • Windows Volume Shadow Copy Service (VSS): The ransomware typically deletes VSS copies to prevent easy recovery. However, in some instances, a previous system restore point or shadow copy might have survived, allowing for limited file restoration. Use vssadmin delete shadows /all /quiet (after system cleanup) to ensure no malicious copies remain, but this also prevents recovery from VSS.

4. Other Critical Information

  • Additional Precautions:

    • Ransom Note: The _readme.txt file is the primary way the attackers communicate, detailing the ransom amount (typically $490-$980 USD, often increasing if not paid within 72 hours) and the contact email ([email protected]). It will also include the victim’s personal ID.
    • Command and Control (C2) Communication: While infecting, the ransomware attempts to communicate with C2 servers to send victim IDs and retrieve encryption keys (for online keys). Firewall rules blocking suspicious outbound connections can sometimes prevent the full encryption process, but this is rare.
    • Self-Deletion/Persistence: After encryption, the ransomware typically attempts to delete its own executable to hinder forensic analysis. It might also attempt to establish persistence mechanisms, so a thorough system scan is vital.
    • Hosts File Modification: Some STOP/Djvu variants may modify the Windows hosts file to block access to cybersecurity websites or forums where victims might seek help. Check C:\Windows\System32\drivers\etc\hosts for any unusual entries.

  • Broader Impact:

    • Data Loss: The most immediate impact is the irreversible loss of encrypted data if decryption is not possible and backups are unavailable.
    • Operational Disruption: For organizations, ransomware attacks can halt operations, productivity, and critical services, leading to significant financial losses beyond the ransom itself.
    • Financial Costs: This includes potential ransom payments (not recommended), costs associated with IT recovery, system restoration, potential consulting fees for cybersecurity experts, and reputation damage.
    • Re-infection Risk: If the initial infection vector (e.g., pirated software source) is not identified and avoided, there is a high risk of re-infection with this or other malware.

By understanding the nature of *id=*2uj**[email protected]*.lazarus as a STOP/Djvu variant, individuals and organizations can better prepare, prevent, and respond to such threats.