known ransomware use

RARLAB WinRAR Code Execution Vulnerability

Added to KEV
2023-08-24
Federal due date
2023-09-14
Vendor
RARLAB
Product
WinRAR
EPSS
99.9th percentile (score 0.939, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Known
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2023-38831

CISA short description

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.

Required action

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.