Applied Cybernetics Group
Threat intel → detection pipeline
Friday, September 18, 2026
Data as of 13:09 UTC

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 0.980, as of 2026-09-16)
NVD CVSS v3.1
7.8 (HIGH)
Ransomware use
Known
ATT&CK
T1005 , T1041 , T1053 , T1059.004 , T1105 , T1112 , T1204 , T1486 · signal rollup
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.

NVD description

RARLAB WinRAR before 6.23 allows attackers to execute arbitrary code when a user attempts to view a benign file within a ZIP archive. The issue occurs because a ZIP archive may include a benign file (such as an ordinary .JPG file) and also a folder that has the same name as the benign file, and the contents of the folder (which may include executable content) are processed during an attempt to access only the benign file. This was exploited in the wild in April through October 2023.

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.