What’s Vulnerable › Vulnerabilities

CVE-2026-91960: FreeRDP before 3.31.0 Integer Overflow Double Free

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-09-15 · updated 2026-09-24
• Weakness: CWE-190

Description

FreeRDP versions before 3.31.0 contain an integer overflow in WinPR's Stream_EnsureRemainingCapacity function that allows remote attackers to cause denial of service. A malicious RD Gateway peer can send a WebSocket Ping frame with a crafted 64-bit extended payload length to trigger integer wraparound, resulting in a double free that crashes the FreeRDP client during connection.

Affected products

• FreeRDP: before 3.31.0 — fixed in 3.31.0

How to fix

Upgrade to a fixed version: FreeRDP 3.31.0. Check the vendor advisory for mitigations.

References

• https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vccg-35r5-8jrf
• https://www.vulncheck.com/advisories/freerdp-before-3.31.0-integer-overflow-double-free
• https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vccg-35r5-8jrf

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