VolkLocker ransomware, attributed to the pro-Russian hacktivist group CyberVolk (aka GLORIAMIST), surfaced in August 2025 as a ransomware-as-a-service platform targeting both Windows and Linux environments. Written in Golang, it uses AES-256 encryption in Galois/Counter Mode (GCM) to encrypt victim files, appending custom extensions like .locked or .cvolk. Operators configure payloads with parameters such as bitcoin address, Telegram bot token, encryption deadline, and self-destruct options. Upon execution, VolkLocker attempts privilege escalation, enumerates system details including virtualization checks, and encrypts files on all drives based on embedded configurations. It modifies Windows Registry to hinder recovery, deletes volume shadow copies, and terminates security processes like Microsoft Defender. A notable enforcement mechanism wipes user folders if ransom is unpaid within 48 hours or if incorrect decryption keys are entered multiple times. However, a critical design flaw was discovered: the ransomware’s master encryption key is hard-coded in the binary and also written in plaintext to a file in the %TEMP% directory (system_backup.key), which is never deleted. This allows victims or defenders to retrieve the key and decrypt files without paying ransom, effectively neutralizing the extortion attempt. CyberVolk manages its RaaS operations via Telegram automation, facilitating victim communication, decryption commands, and system info retrieval. The group also markets additional malware tools like remote access trojans and keyloggers. Despite repeated Telegram bans, CyberVolk has expanded its offerings and continues politically motivated attacks, primarily supporting Russian interests. The ransomware’s implementation lapses reduce its operational threat, but its destructive capabilities and geopolitical context maintain its relevance as a security concern.

For European organizations, VolkLocker presents a mixed threat profile. On one hand, its destructive features—such as deleting shadow copies, disabling antivirus processes, and wiping critical user folders after a deadline—pose significant risks to data availability and operational continuity. Public sector entities, critical infrastructure, and enterprises with sensitive data could face disruption and data loss. On the other hand, the hard-coded master key flaw allows victims to recover encrypted files without paying ransom, mitigating the financial impact and reducing the ransomware’s leverage. However, the presence of this ransomware indicates active targeting by politically motivated threat actors aligned with Russian interests, which may signal broader cyber espionage or sabotage campaigns. The use of Telegram for command-and-control and automation lowers barriers for attackers, potentially increasing attack volume. Organizations relying heavily on Windows and Linux systems, especially those with insufficient endpoint protection or lacking robust backup and recovery strategies, remain vulnerable. The threat also underscores the importance of monitoring emerging RaaS platforms and their evolving tactics. Overall, while the immediate ransom threat is diminished, the operational and geopolitical risks remain significant for European targets.

European organizations should implement targeted mitigations beyond generic ransomware advice. First, proactively monitor for the presence of the plaintext master key file (system_backup.key) in temporary directories to detect and respond to infections early. Deploy endpoint detection and response (EDR) solutions capable of identifying VolkLocker’s behavior patterns, such as privilege escalation attempts, registry modifications, and antivirus process terminations. Harden systems by restricting write permissions to temporary folders and enforcing application whitelisting to prevent unauthorized execution of ransomware binaries. Maintain frequent, immutable backups stored offline or in segregated networks to enable rapid recovery without ransom payment. Network segmentation should be enforced to limit ransomware spread. Given the use of Telegram for command-and-control, monitor outbound network traffic for suspicious connections to Telegram APIs or unusual bot activity. Incident response teams should prepare for potential destructive payloads triggered by enforcement timers and implement rapid containment procedures. Finally, raise user awareness about ransomware tactics and ensure timely patching of vulnerabilities to reduce attack surface. Collaboration with law enforcement and sharing threat intelligence within European cybersecurity communities will enhance collective defense against CyberVolk’s operations.