*[email protected]*.eth.hv88g2

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This document provides a comprehensive overview of the ransomware variant identified by the file extension *[email protected]*.eth.hv88g2. Based on its characteristic file extension pattern, which includes an appended email address and multiple suffixes, this ransomware strongly resembles variants belonging to the STOP/Djvu ransomware family or a closely related derivative. While specific, granular details about the [email protected] variant might be limited due to the rapid evolution of these threats, the general behavior, attack vectors, and recovery strategies are largely consistent with its parent family.

Technical Breakdown:

1. File Extension & Renaming Patterns

  • Confirmation of File Extension: The exact file extension used by this ransomware is .[original_filename]*[email protected]*.eth.hv88g2. This means that after encryption, a file originally named document.docx would be renamed to something like [email protected].
  • Renaming Convention: The ransomware appends a complex string to the original file name. This string typically follows the pattern: .<attacker_email>.<unique_extension>.<unique_id>. In this specific case:
    • [email protected]: This segment likely serves as the attacker’s contact email address, often used by victims to initiate ransom negotiations.
    • .eth: This appears to be a fixed extension appended by this specific variant.
    • .hv88g2: This is a unique identifier, often generated per infection or per batch of encrypted files. Its purpose is to help the attackers identify the victim and the specific decryption key needed.

2. Detection & Outbreak Timeline

  • Approximate Start Date/Period: Ransomware variants using this naming convention (embedding an email and a unique ID) emerge frequently. While *[email protected]*.eth.hv88g2 might be a relatively new or less widely reported specific variant, the underlying STOP/Djvu family has been active since late 2018 and consistently receives new updates and new extensions. New variants like this are typically detected shortly after they begin to appear in the wild, often within days or weeks of their initial deployment. Without specific threat intelligence for “frazeketcham,” we can infer its emergence is recent, within the last few months, given the rapid rotation of email addresses and identifiers by these groups.

3. Primary Attack Vectors

Like other STOP/Djvu variants, *[email protected]*.eth.hv88g2 primarily relies on:

  • Software Bundling/Cracked Software: This is the most prevalent method. The ransomware is often bundled with pirated software, cracked games, fake software installers, or malicious keygens and activators downloaded from dubious websites (e.g., torrent sites, free software download sites, warez forums). When a user attempts to install the “cracked” software, the ransomware executes in the background.
  • Phishing Campaigns: While less common for the main distribution of STOP/Djvu, targeted phishing emails containing malicious attachments (e.g., fake invoices, shipping notifications, resumes) or links to compromised websites can also be used.
  • Malvertising/Compromised Websites: Drive-by downloads from compromised legitimate websites or malicious advertisements that redirect users to exploit kits, though less common for direct Djvu distribution, remain potential avenues.
  • Fake Updates: Prompts for fake software updates (e.g., Flash Player, browser updates) that actually download the ransomware.
  • Remote Desktop Protocol (RDP) Exploits: While not a primary vector for initial infection with STOP/Djvu, weak or exposed RDP credentials can allow attackers to gain access to a system and manually deploy the ransomware.

Remediation & Recovery Strategies:

1. Prevention

  • Regular Backups: Implement a robust 3-2-1 backup strategy (3 copies of data, on 2 different media, with 1 copy off-site/offline). Ensure backups are isolated from the network to prevent encryption. This is the single most effective defense.
  • Software Updates: Keep your operating system, web browsers, antivirus software, and all other applications up-to-date with the latest security patches.
  • Antivirus/Endpoint Protection: Use reputable antivirus or endpoint detection and response (EDR) solutions with real-time protection and behavioral analysis capabilities. Keep definitions updated.
  • Firewall Configuration: Configure your firewall to block unauthorized incoming and outgoing connections.
  • User Account Control (UAC): Do not disable UAC on Windows systems.
  • Email Security: Exercise extreme caution with email attachments and links, especially from unknown senders. Implement email filtering solutions.
  • Educate Users: Train users to identify phishing attempts, avoid downloading software from untrusted sources, and be wary of suspicious links and attachments.
  • Disable SMBv1: If not strictly necessary, disable Server Message Block version 1 (SMBv1) protocol on Windows systems as it has known vulnerabilities exploited by some ransomware.
  • Strong Passwords & MFA: Use strong, unique passwords for all accounts and enable Multi-Factor Authentication (MFA) wherever possible, especially for RDP and critical services.

2. Removal

  • Isolate the Infected System: Immediately disconnect the infected computer from the network (unplug Ethernet cable, disable Wi-Fi) to prevent further spread to other devices.
  • Identify Ransomware Processes: Use Task Manager (Windows) or process monitoring tools to identify suspicious processes. Ransomware often runs from temporary folders or hidden directories.
  • Boot into Safe Mode: Restart the computer in Safe Mode (with Networking, if needed for tool downloads) to prevent the ransomware from executing its payload fully.
  • Scan with Antivirus/Anti-Malware: Perform a full system scan using a reputable and updated antivirus/anti-malware program (e.g., Malwarebytes, Windows Defender, ESET, Bitdefender). It’s advisable to use a different scanner than the one that failed to prevent the infection.
  • Remove Detected Threats: Allow the antivirus/anti-malware software to quarantine or delete all detected ransomware components, malicious files, and associated registry entries.
  • Check for Persistence Mechanisms: Manually check common ransomware persistence locations (e.g., Startup folders, Registry Run keys, Scheduled Tasks, WMI event subscriptions) and remove any entries related to the ransomware.
  • Change Passwords: Once the system is clean, change all system and network passwords, especially if they were stored or used on the compromised machine.

3. File Decryption & Recovery

  • Recovery Feasibility: For most recent STOP/Djvu variants, including those with extensions like *[email protected]*.eth.hv88g2, decryption without the attacker’s key is generally NOT possible. This is because these variants typically use a combination of strong encryption algorithms (e.g., Salsa20, AES) and online keys, meaning a unique key is generated for each victim and transmitted to the attackers’ server.
    • Offline Keys: In rare cases (e.g., if the ransomware failed to connect to its C2 server), an “offline key” might be used. For such instances, tools like the Emsisoft Decryptor for STOP/Djvu might be able to decrypt files. However, this relies on Emsisoft’s researchers having previously obtained the specific offline key for your variant. You can submit encrypted files to Emsisoft’s analysis service to check for decryptability.
  • Essential Tools/Patches:
    • Emsisoft Decryptor for STOP/Djvu: This is the primary tool to attempt decryption if an offline key matches. Download it directly from Emsisoft’s official website.
    • ShadowExplorer: This tool can help you recover previous versions of files (Shadow Copies) if they were not deleted by the ransomware. Many ransomware variants, including Djvu, attempt to delete Shadow Copies, so success is not guaranteed.
    • Data Recovery Software: Tools like PhotoRec, Recuva, or Disk Drill might recover some unencrypted fragments of files, especially if the original files were only partially overwritten or deleted before encryption. Success varies widely.
    • System Restore Points: If enabled, you might be able to revert your system to a previous state, but this will not decrypt files already encrypted and should only be done after thoroughly cleaning the infection.
  • Best Recovery Method: Backups: The most reliable method to recover your files is to restore them from clean, isolated backups created before the infection.

4. Other Critical Information

  • Additional Precautions:
    • Fake Decryptors: Be extremely wary of websites or services claiming to offer immediate decryption for a fee or requiring you to download a “special tool.” These are often scams that might install further malware or simply take your money without providing a solution.
    • Ransom Notes: This variant will typically drop ransom notes named _readme.txt (or similar) in every folder containing encrypted files. These notes will contain instructions on how to contact the attackers (likely via the [email protected] email or similar) and how to pay the ransom.
    • Information Stealer: A critical characteristic of the STOP/Djvu family is that it often deploys an information-stealing malware (e.g., Vidar, RedLine Stealer) before encryption. This stealer attempts to exfiltrate sensitive data such as browser passwords, cryptocurrency wallet information, and other personal files. Even if you recover your files from backups, assume your credentials have been compromised and change all critical passwords (especially for banking, email, and social media) immediately on a clean device.
  • Broader Impact:
    • Financial Loss: Direct ransom payments, lost productivity, and costs associated with system cleanup and data recovery.
    • Data Loss: If backups are insufficient or corrupted, permanent data loss can occur.
    • Privacy Compromise: The inclusion of information-stealing malware means that beyond file encryption, victims’ sensitive personal and financial data may have been exfiltrated, leading to potential identity theft or further targeted attacks.
    • Reputational Damage: For businesses, a ransomware attack can severely damage reputation and customer trust.
    • Resource Drain: Significant IT resources are often required to respond to and recover from an attack, diverting attention from core business operations.

By understanding the technical aspects and implementing robust prevention and recovery strategies, individuals and organizations can significantly reduce their risk and mitigate the impact of ransomware like *[email protected]*.eth.hv88g2.