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UK Cyber Defence
VulnerabilityAnalyzed

CVE-2023-38831

RARLAB WinRAR Code Execution Vulnerability

KEVHIGH 7.8EPSS 97.9%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 14 September 2023). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

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.

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
97.89% probability · 100th percentile
CISA KEV
Listed 24 August 2023 · due 14 September 2023 · used in ransomware campaigns
Weakness
CWE-345, CWE-351
Affected
rarlab/winrar
Source
cve@mitre.org

CISA notes

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. http://www.win-rar.com/singlenewsview.html?&L=0&tx_ttnews%5Btt_news%5D=232&cHash=c5bf79590657e32554c6683296a8e8aa; https://nvd.nist.gov/vuln/detail/CVE-2023-38831

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.