APT41-Linked Amaranth Dragon Exploits WinRAR CVE-2025-8088 in Espionage Campaign

APT41-Linked Threat Actor Exploits WinRAR Zero-Day in Targeted Espionage

A newly identified cyberespionage group, Amaranth Dragon, with ties to the Chinese state-sponsored APT41, has exploited CVE-2025-8088, a critical vulnerability in WinRAR, to conduct targeted attacks against government and law enforcement agencies. The flaw, which remains under active exploitation, enables threat actors to execute arbitrary code on vulnerable systems.

Technical Details of CVE-2025-8088

CVE-2025-8088 is a remote code execution (RCE) vulnerability affecting WinRAR versions prior to 7.0.1, a widely used file archiving utility. The flaw stems from an improper path traversal issue in WinRAR’s handling of specially crafted archive files, allowing attackers to drop malicious payloads in sensitive system directories, such as the Windows Startup folder.

Once exploited, the vulnerability enables threat actors to:

• Execute arbitrary commands with user-level privileges
• Deploy additional malware for persistence and lateral movement
• Exfiltrate sensitive data from compromised systems

Security researchers note that the attack chain leverages phishing emails containing weaponized archives, which, when opened, trigger the exploit without further user interaction.

Impact and Attribution

Amaranth Dragon’s campaign aligns with APT41’s historical targeting patterns, focusing on government, defense, and law enforcement entities across Southeast Asia and North America. While attribution remains challenging, overlapping tactics, techniques, and procedures (TTPs)—including the use of custom malware families and infrastructure reuse—strongly suggest a connection to the Chinese advanced persistent threat (APT) group.

The exploitation of CVE-2025-8088 underscores the growing trend of state-sponsored actors weaponizing widely deployed software to bypass traditional security controls. Given WinRAR’s 500+ million user base, the vulnerability poses a significant risk to organizations relying on the tool for file compression and extraction.

Mitigation and Recommendations

Security teams are urged to take immediate action to mitigate risks associated with CVE-2025-8088:

1. Patch Management

   • Upgrade to WinRAR 7.0.1 or later to eliminate the vulnerability.
   • Deploy automated patch management tools to ensure timely updates across all endpoints.

2. Email Security

   • Block or quarantine archive files (.RAR, .ZIP) from untrusted sources.
   • Implement sandboxing solutions to analyze suspicious attachments before delivery.

3. Endpoint Protection

   • Enforce application whitelisting to prevent unauthorized execution of WinRAR or other archiving tools.
   • Monitor for unusual process activity, particularly in the Startup folder or other auto-execution paths.

4. Threat Hunting

   • Search for indicators of compromise (IOCs) associated with Amaranth Dragon, including:
     • Malicious archive files with anomalous structures
     • Unusual network connections to known APT41 command-and-control (C2) servers
     • Persistence mechanisms in registry keys or scheduled tasks

5. User Awareness

   • Conduct phishing simulation exercises to train employees on recognizing malicious attachments.
   • Emphasize the risks of opening unsolicited archives, even from seemingly legitimate sources.

Conclusion

The exploitation of CVE-2025-8088 by Amaranth Dragon highlights the critical need for proactive vulnerability management in high-risk sectors. Organizations must prioritize patch hygiene, email security, and endpoint monitoring to defend against sophisticated cyberespionage campaigns. As state-sponsored threat actors continue to refine their tactics, security teams should remain vigilant for emerging zero-days in widely used software.

For further details, refer to the original report by BleepingComputer.