CVE-2026-91963

FreeRDP versions before 3.31.0 contain an uninitialized heap memory disclosure vulnerability in the urbdrc USB redirection channel. A malicious RDP server can induce failing USB transfers to read uninitialized heap memory from the client, defeating ASLR and enabling remote code execution when chained with memory corruption vulnerabilities.

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 HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-hw7p-5h2r-83gq	Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-2.0.0-through-3.30.0-uninitialized-heap-memory-disclosure-via-urbdrc	Third Party Advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-hw7p-5h2r-83gq	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

23 Sep 2026, 20:08

Type	Values Removed	Values Added
References	~~() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-hw7p-5h2r-83gq -~~	() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-hw7p-5h2r-83gq - Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/freerdp-2.0.0-through-3.30.0-uninitialized-heap-memory-disclosure-via-urbdrc -~~	() https://www.vulncheck.com/advisories/freerdp-2.0.0-through-3.30.0-uninitialized-heap-memory-disclosure-via-urbdrc - Third Party Advisory
CPE		cpe:2.3:a:freerdp:freerdp::::::::
First Time		Freerdp freerdp Freerdp

Information

Published : 2026-09-15 16:17

Updated : 2026-09-23 20:08

NVD link : CVE-2026-91963

Mitre link : CVE-2026-91963

CVE.ORG link : CVE-2026-91963

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-457

Use of Uninitialized Variable

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