Known exploited · RARLAB
CVE-2023-38831: RARLAB WinRAR Code Execution Vulnerability
What it is
RARLAB WinRAR contains an unspecified vulnerability that allows an attacker to execute code when a user attempts to view a benign file within a ZIP archive.
- Vendor
- RARLAB
- Product
- WinRAR
- Added to KEV
- August 24, 2023
- CISA due date
- September 14, 2023
- Ransomware use
- Known
What CISA requires
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Forensic triage
No
What to do now
- Find every instance of WinRAR you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before September 14, 2023 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.