A New Threat Demands Your Attention: WinRAR’s Zero-Day Flaw, Exploited in the Wild, Here’s What You Must Do
Recently, security researchers at ESET uncovered a serious zero-day vulnerability (CVE-2025-8088) in WinRAR’s Windows components, like RAR, UnRAR.dll, and the portable UnRAR code, that’s already being weaponized through phishing campaigns. This path-traversal weakness allows attackers to force WinRAR to use hidden file paths embedded in malicious archives, letting them deposit backdoor malware silently into critical system folders, such as the Startup directory.
“When extracting a file, previous versions of WinRAR, Windows versions of RAR, UnRAR, portable UnRAR source code and UnRAR.dll can be tricked into using a path, defined in a specially crafted archive, instead of a specified path.” – WinRAR
Why It Matters
Groups like RomCom, also referred to as Storm-0978, UNC2596, or Paper Werewolf, are exploiting these vulnerable archives via spear-phishing to place malware that launches automatically at startup . Granted, WinRAR has released version 7.13 to patch this, but because WinRAR lacks an auto-update mechanism, many users remain exposed .
Look Back to Move Forward
Just a few months earlier, in June 2025, another WinRAR flaw, CVE-2025-6218, also enabled directory traversal and remote code execution due to improper path handling. This reveals a troubling pattern: attackers are finding and exploiting path-based flaws in WinRAR to gain unauthorized access.
Your Next Steps; Be Proactive, Be Protected
| Step | Action | Why It’s Essential |
|---|---|---|
| 1. Update Immediately | Upgrade to WinRAR version 7.13 manually, since it fixes both CVE-2025-8088 and earlier CVE-2025-6218. | It’s your most effective defense, no update means you remain vulnerable. |
| 2. Treat Archives with Suspicion | Never open RAR files or archives from unknown or unexpected sources. | Phishing emails are the primary infection path. |
| 3. Use Security Layers | Scan archives with updated antivirus or endpoint protection before extraction. | Early detection can block malicious payloads before they execute. |
| 4. Monitor Startup Changes | Check for any odd new files in system startup locations or unexpected executables. | If compromised, this helps catch unwanted persistence early. |
| 5. Educate Your Team | If you’re in a professional setting, inform colleagues about this threat and how it works. | Awareness is your strongest ally in preventing successful attacks. |
In Summary, Tell It Like It Is
Yes, this situation is serious, and yes, it’s urgent. But the fix is straightforward: update WinRAR 7.13 now, treat suspicious archives as potential threats, and layer your protection. Don’t assume safety through obscurity, attackers are already exploiting this flaw. Stay sharp, stay secure.