Integer overflow in Freerdp
CVE-2026-91960
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.
Vulnerability class: Integer Overflow
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.
Affected products
Weakness classification (CWE)
References
- disclosure@vulncheck.com (vendor-advisory)
- disclosure@vulncheck.com (third-party-advisory)
Frequently asked questions
- What is CVE-2026-91960?
- CVE-2026-91960 is a medium-severity vulnerability in Freerdp, classified under Integer Overflow or Wraparound. CVSS score: 6.5/10. Published 2026-09-15.
- How severe is CVE-2026-91960?
- Medium severity. CVSS v3 base score is 6.5 out of 10.