How severe is CVE-2023-38831?

CVE-2023-38831 has a CVSS score of 7.8/10, rated HIGH. Immediate patching is strongly recommended.

Which products are affected by CVE-2023-38831?

Affected package information for CVE-2023-38831 is not yet fully mapped. Check the official advisory links for details.

How do I patch CVE-2023-38831?

Apply the rarlab winrar security patch or hotfix for CVE-2023-38831 on the affected version, following the vendor advisory for your exact build.

How do I detect CVE-2023-38831 across my infrastructure?

Inventory every rarlab winrar deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for remote code execution at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.

How do I mitigate CVE-2023-38831 if there is no patch (or I can't update yet)?

Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.

How does O3 Security protect against CVE-2023-38831?

O3 detects and blocks CVE-2023-38831 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.

Is CVE-2023-38831 actively exploited in the wild?

Yes. There are 53 known exploit references for CVE-2023-38831, including 31 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2023-38831?

CVE-2023-38831 has an EPSS (Exploit Prediction Scoring System) score of 97.8%, placing it in the 100th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is CVE-2023-38831 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2023-38831 (RARLAB WinRAR Code Execution Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2023-08-24. CISA required all US federal civilian agencies to remediate this vulnerability by 2023-09-14. The required action was: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. This CVE has been used in known ransomware campaigns. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2023-38831?

CVE-2023-38831 is classified as CWE-345 (CWE-345), CWE-351 (CWE-351). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

Which products and versions are affected by CVE-2023-38831?

CVE-2023-38831 affects rarlab winrar. Check the affected-products list on this page against your deployed version to confirm exposure.

Is there exploit tooling available for CVE-2023-38831?

2 Metasploit modules reference CVE-2023-38831, which lowers the barrier to weaponization. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2023-38831 published, and has it been updated?

CVE-2023-38831 was published on August 23, 2023 and was last updated on June 17, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CISA KEV·Added 2023-08-24 — agencies required to remediate by 2023-09-14 · Ransomware

CVE-2023-38831

HIGH

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…

Published

Aug 23, 2023

Updated

Jun 17, 2026

Affected

0 pkgs

Patched

None yet

Exploits

53 known

EPSS Exploitation Probability

via FIRST.org ↗

97.8%probability of exploitation in next 30 days

Very High Risk100th percentile0.00%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

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.

Affected Products

1 product · 1 configurations

Application

winrarrarlab

< 6.23

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.