Zero-day vulnerability in WinRAR: how it is exploited and how…

On August 11, 2025, ESET researchers made public the discovery of a zero-day vulnerability in WinRAR that was being actively exploited. This flaw allows attackers to execute malicious code by decompressing specially crafted files.

What do we know about CVE-2025-8088?

• Discovery and exploitation: On July 18, 2025, an exploit was detected that took advantage of a path traversal flaw in WinRAR. Attackers would hide malicious files inside RAR archives and deploy them when the victim extracted them.
• Responsible: The Russian-linked RomCom group used this vulnerability in campaigns targeting financial, manufacturing, defense and logistics sectors.
• Official recognition: the vulnerability is registered as CVE-2025-8088; WinRAR released a corrected version (7.13) on July 30.

Recommendations for users and companies

1. Update WinRAR: install version 7.13 or higher; older versions (including command-line utilities and UnRAR.dll) are vulnerable.
2. Check compressed files: Avoid extracting RAR files from unknown senders; scan the files with an updated antivirus.
3. Enforce email policies: Set up filters to block suspicious attachments and train employees to recognize potentially dangerous files.
4. Monitor critical systems: If you have used vulnerable versions, check systems for backdoors associated with SnipBot, RustyClaw, or the Mythic agent.

Summary of Key Security Takeaways and Actionable Guidelines

To maintain highest standards of operational resilience and cybersecurity compliance across corporate systems, organizations must adopt a proactive security stance. Continuous security testing, strict threat modeling, automated auditing pipelines, and adherence to established international frameworks (such as NIST FIPS PUB 180-4, OWASP recommendations, and CISA advisories) form the cornerstone of modern digital protection.

By systematically applying least-privilege principles, cryptographically verifying data assets, and isolating high-risk compute workloads within zero-trust boundaries, security teams can effectively mitigate emergent threats while sustaining long-term technological innovation.

Conclusion

The CVE-2025-8088 vulnerability demonstrates that even popular tools like WinRAR can become an attack vector. Keeping software up to date and following good digital hygiene practices are key to minimizing risk.