CVE-2026-91961

FreeRDP before 3.31.0 contains a denial-of-service vulnerability in the URBDRC control-transfer request path that fails to validate OutputBufferSize before forwarding to the libusb backend. A malicious RDP server can send a control-transfer request with OutputBufferSize set to 65536, triggering a reachable assertion that terminates the client process.

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-w9qg-g24r-77f6	Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-before-3.31.0-denial-of-service-via-urbdrc	Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

23 Sep 2026, 20:02

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-w9qg-g24r-77f6 -~~	() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-w9qg-g24r-77f6 - Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/freerdp-before-3.31.0-denial-of-service-via-urbdrc -~~	() https://www.vulncheck.com/advisories/freerdp-before-3.31.0-denial-of-service-via-urbdrc - Third Party Advisory

Information

Published : 2026-09-15 16:17

Updated : 2026-09-23 20:02

NVD link : CVE-2026-91961

Mitre link : CVE-2026-91961

CVE.ORG link : CVE-2026-91961

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-617

Reachable Assertion

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