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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vccg-35r5-8jrf	Exploit Mitigation Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-before-3.31.0-integer-overflow-double-free	Third Party Advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vccg-35r5-8jrf	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*

History

24 Sep 2026, 12:17

Type	Values Removed	Values Added
CPE		cpe:2.3:a:freerdp:freerdp::::::::
References	~~() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vccg-35r5-8jrf -~~	() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vccg-35r5-8jrf - Exploit, Mitigation, Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/freerdp-before-3.31.0-integer-overflow-double-free -~~	() https://www.vulncheck.com/advisories/freerdp-before-3.31.0-integer-overflow-double-free - Third Party Advisory
First Time		Freerdp freerdp Freerdp

Information

Published : 2026-09-15 16:17

Updated : 2026-09-24 12:17

NVD link : CVE-2026-91960

Mitre link : CVE-2026-91960

CVE.ORG link : CVE-2026-91960

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-190

Integer Overflow or Wraparound

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