*[email protected]*.lock

[Content by Gemini 2.5]

This report provides a comprehensive overview of the ransomware variant identified by the file extension *[email protected]*.lock. While specific details can sometimes vary between campaigns, the general characteristics and recommended strategies remain consistent for variants utilizing this naming convention.

Technical Breakdown:

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: The exact file extension used by this ransomware is [email protected].
  • Renaming Convention: This ransomware follows a common renaming pattern. It appends the string .[[email protected]].lock to the original filename and extension.
    • Example: A file named document.docx would be renamed to [email protected].
    • Similarly, photo.jpg would become [email protected].
      This pattern is highly indicative of ransomware families like Dharma (also known as Dharma/Gharial or Phobos, although the specific email address is the differentiating factor in campaigns).

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: Variants using email addresses within their file extensions, such as this one, are typically associated with established ransomware families like Dharma or Phobos. These families have been active since at least 2016-2017, with new specific email-based campaigns emerging frequently. The [email protected] specific campaign likely started appearing in late 2022 or early 2023, as new contact emails are regularly adopted by threat actors. These types of ransomware are continually updated and propagated by various affiliate groups.

3. Primary Attack Vectors

The *[email protected]*.lock variant, like many similar ransomware types, primarily utilizes the following propagation mechanisms:

  • Remote Desktop Protocol (RDP) Exploitation: This is one of the most common vectors. Attackers gain access to systems with weak or exposed RDP configurations, often through brute-force attacks or by using compromised credentials purchased from dark web markets. Once inside, they manually deploy the ransomware.
  • Phishing Campaigns: Malicious emails containing infected attachments (e.g., weaponized documents, archives with executables) or links to malicious websites that deliver the payload. These emails often impersonate legitimate entities or offer tempting content.
  • Exploitation of Software Vulnerabilities: Unpatched software, operating systems, or network services (e.g., unpatched VPNs, web servers, or applications) can be exploited to gain initial access and deploy the ransomware. While less common for this specific type of ransomware compared to worms like WannaCry, it remains a viable vector for initial breach.
  • Supply Chain Attacks/Third-Party Software: In some cases, ransomware can be delivered through compromised legitimate software updates or bundled with trojanized versions of popular applications downloaded from unofficial sources.
  • Compromised Credentials: Stolen or leaked credentials (e.g., via infostealers, previous breaches) can be used to log into corporate networks and deploy the ransomware directly.

Remediation & Recovery Strategies:

1. Prevention

  • Robust Backup Strategy: Implement a 3-2-1 backup rule (3 copies of data, on 2 different media, with 1 copy off-site/offline). Regularly test backup restoration processes. Ensure backups are isolated from the network to prevent encryption.
  • Patch Management: Keep all operating systems, applications, and network devices fully updated with the latest security patches. Prioritize patches for known vulnerabilities, especially those affecting RDP, VPNs, and common server software.
  • Strong Authentication & MFA: Enforce strong, unique passwords for all accounts. Implement Multi-Factor Authentication (MFA) for all remote access services (RDP, VPNs), administrative accounts, and critical systems.
  • Network Segmentation: Segment your network to limit lateral movement. Isolate critical systems and sensitive data.
  • Endpoint Detection and Response (EDR) / Antivirus (AV): Deploy and maintain next-generation antivirus/EDR solutions on all endpoints and servers. Ensure they are configured for real-time protection and regularly updated.
  • Principle of Least Privilege: Grant users and applications only the minimum necessary permissions to perform their functions.
  • User Awareness Training: Educate employees about phishing, social engineering tactics, and safe internet practices.
  • Harden RDP: Disable RDP if not strictly necessary. If RDP is required, place it behind a VPN, use strong passwords/MFA, limit access to specific IP addresses, and monitor RDP logs for unusual activity.

2. Removal

  • Isolate Infected Systems: Immediately disconnect any compromised systems from the network (physically or logically) to prevent further spread.
  • Identify Ransomware Processes: Use task manager, process explorer, or security tools to identify and terminate any running ransomware processes. Be cautious, as some ransomware may attempt to delete shadow copies or security tools.
  • Run Full System Scans: Boot the infected system into Safe Mode (if possible) or use a bootable antivirus rescue disk. Perform a full system scan with a reputable and updated antivirus/anti-malware solution. Examples include Malwarebytes, ESET, or other major vendors.
  • Check Startup Items and Scheduled Tasks: Verify and remove any suspicious entries in system startup folders, registry run keys, or scheduled tasks that could re-launch the ransomware.
  • Restore from Backup: The safest and most reliable way to recover is to wipe the infected system (reformat and reinstall the OS) and restore data from clean, uninfected backups. This ensures complete removal of the ransomware and any potential backdoors.

3. File Decryption & Recovery

  • Recovery Feasibility: For the *[email protected]*.lock variant (typical of Dharma/Phobos campaigns), direct decryption without the attacker’s private key is generally not possible. These ransomware families typically use strong encryption algorithms (e.g., AES-256 and RSA-2048) that are computationally infeasible to break without the key.

    • No More Ransom Project: Always check the No More Ransom website. This collaborative initiative offers free decryption tools for many ransomware families. While a specific tool for [email protected] might not exist at all times (as new campaigns emerge), tools for the underlying Dharma or Phobos family might be available, which might work if the specific variant uses a known vulnerability or common key.
    • Backups are Paramount: The most reliable method of file recovery is through clean, verified backups.
    • Shadow Copies: The ransomware often attempts to delete Volume Shadow Copies (VSS) to prevent easy restoration. However, it’s always worth attempting to restore previous versions of files or folders via Windows’ built-in functionality, as the deletion might not always be successful or complete.

  • Essential Tools/Patches:

    • Reputable Antivirus/EDR solutions: For detection and removal (e.g., CrowdStrike, SentinelOne, Microsoft Defender for Endpoint, ESET, Bitdefender).
    • Backup Solutions: Reliable software/hardware for creating and managing backups.
    • Operating System & Application Updates: Keep Windows Update, third-party software (browsers, office suites, PDF readers, Java, Adobe products), and server software up-to-date.
    • Network Monitoring Tools: For detecting suspicious RDP connections or unusual network traffic.
    • Password Managers: To enforce strong, unique passwords.

4. Other Critical Information

  • Additional Precautions:

    • Ransom Note: This variant typically leaves ransom notes (e.g., info.txt, README.txt, _FILES_INFO_.txt, FILES ENCRYPTED.txt) on the desktop and in directories containing encrypted files. These notes provide instructions on how to contact the attackers via the specified email address ([email protected]) to negotiate decryption. Do not engage with the attackers if you have reliable backups.
    • Persistence Mechanisms: The ransomware may attempt to create persistence mechanisms (e.g., new user accounts, scheduled tasks, registry modifications) to re-execute itself or provide backdoor access. Thorough post-infection checks are crucial.
    • Information Stealing: While not explicitly a characteristic of all Dharma/Phobos variants, some ransomware operations also exfiltrate data before encryption. Assume this possibility and check for suspicious outbound network activity.
    • No Guarantees: Even if you pay the ransom, there is no guarantee that the attackers will provide a working decryptor or that all files will be recovered. Paying also funds future criminal activities.

  • Broader Impact:

    • Data Loss: Primary impact is the loss of access to critical data, potentially permanently if backups are unavailable or compromised.
    • Business Disruption: Significant downtime for organizations, leading to lost productivity, revenue, and customer trust.
    • Financial Costs: Recovery efforts involve considerable financial investment in IT resources, security upgrades, and potential professional incident response services.
    • Reputational Damage: For businesses, a ransomware attack can severely damage public image and trust.
    • Supply Chain Risk: If a vendor or partner is infected, it can have ripple effects on interconnected businesses.

This *[email protected]*.lock ransomware variant, while not unique in its methodology, represents a persistent threat that preys on common security vulnerabilities. Proactive prevention and robust recovery planning are your strongest defenses.