CVE-2023-38831: in the CISA KEV catalogue
RARLAB WinRAR Code Execution Vulnerability. CISA added CVE-2023-38831 to the Known Exploited Vulnerabilities catalogue on 2023-08-24 with a default due date of 2023-09-14. Known ransomware campaign use: Known. Forensic triage flag: No.
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. (CISA description)
- Vendor / product
- RARLAB WinRAR
- CWE
- CWE-351
- CISA required action
- Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- EPSS
- 100%, percentile 99 (scored 2026-11-03)
EPSS puts nearly every time in 100 odds (100%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 99% of scored CVEs. This is a model estimate about exploitation anywhere, not about your environment.
Vendor and reference links (from CISA)
Your own deadline under CISA BOD 26-04 depends on exposure, automatability and technical impact: work it out with the BOD 26-04 calculator.
Frequently asked questions
Is CVE-2023-38831 in the CISA KEV catalogue?
Yes. CISA added CVE-2023-38831 (RARLAB WinRAR Code Execution Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2023-08-24. CISA's default due date for it is 2023-09-14.
Is CVE-2023-38831 used in ransomware attacks?
CISA marks known ransomware campaign use as Known for CVE-2023-38831.
What should I do about CVE-2023-38831?
CISA's required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Sources
- CISA, Known Exploited Vulnerabilities Catalog (accessed 2026-11-03)
- FIRST, Exploit Prediction Scoring System (EPSS) (EPSS by FIRST; scores generated by Empirical Security)
- NVD record for CVE-2023-38831