IRONSMITHINTEL
HIGHCVSS7.8
|
Actively Exploited
|CISA KEV|CVE-2023-38831|Auth: none — unauthenticated|Reboot: required|Manual only

RARLAB WinRAR Code Execution Vulnerability (CVE-2023-38831)

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.

Published Aug 23, 2023 · Updated May 29, 2026
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Why patchRisk explained in plain English
Worst-case scenarioIf unpatched

A local attacker, without authentication, can achieve full data confidentiality loss, arbitrary modification of data, complete denial of service or system unavailability. CISA has confirmed use of this vulnerability in known ransomware campaigns — treat as high priority for remediation. Federal agencies are required to remediate by 2023-09-14 under CISA BOD 22-01.

How the attack worksNo clicks needed

This is a Software Vulnerability (CWE-345) (CWE-345) vulnerability in RARLAB WinRAR. Exploitation requires local access, low attack complexity, no authentication required, and user interaction required.

Am I affected?Quick check

Probably yes if any of these apply:

●IT Security
●Running winrar: v < 6.23
Real-world incidentsWhat we've seen

Used in known ransomware campaigns. Threat-research write-up: http://packetstormsecurity.com/files/174573/WinRAR-Remote-Code-Execution.html

How to patch

Manual remediation steps

Apply the Vendor Patch

This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.

CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

References

    1
    Vendor advisory: http://www.win-rar.com/singlenewsview.html?&L=0&tx_ttnews%5Btt_news%5D=232&cHash=c5bf79590657e32554c6683296a8e8aa
    1
    NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2023-38831
    1
    CISA KEV: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-38831
PowerShell automationComing soon

No tested PowerShell script for this entry yet. We’re prioritising automation based on user demand.

References

↗ CVE-2023-38831↗ Advisory

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