CVE-2026-91951

FreeRDP versions before 3.31.0 contain an out-of-bounds write vulnerability in the urbdrc client channel's urb_send_current_frame_number_result() function. A malicious RDP server can send a crafted 28-byte USB redirection message to trigger a 4-byte write past the allocated 16-byte buffer, causing denial of service when verbose asserts are enabled.

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-h5w2-q35j-443h	Exploit Mitigation Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-3.14.0-through-3.30.0-out-of-bounds-write-via-urbdrc	Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

24 Sep 2026, 12:15

Type	Values Removed	Values Added
CPE		cpe:2.3:a:freerdp:freerdp::::::::
First Time		Freerdp freerdp Freerdp
References	~~() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-h5w2-q35j-443h -~~	() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-h5w2-q35j-443h - Exploit, Mitigation, Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/freerdp-3.14.0-through-3.30.0-out-of-bounds-write-via-urbdrc -~~	() https://www.vulncheck.com/advisories/freerdp-3.14.0-through-3.30.0-out-of-bounds-write-via-urbdrc - Third Party Advisory

Information

Published : 2026-09-15 16:17

Updated : 2026-09-24 12:15

NVD link : CVE-2026-91951

Mitre link : CVE-2026-91951

CVE.ORG link : CVE-2026-91951

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-617

Reachable Assertion

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