CVE-2026-91954

FreeRDP before 3.31.0 contains a null pointer dereference vulnerability in gdi_surface_bits when processing Surface Bits commands with NSCodec codec ID. A malicious RDP server can crash a FreeRDP client by sending a crafted Surface Bits command claiming to use NSCodec, even when the codec is disabled.

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-ffjr-p229-hpch	Exploit Mitigation Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-before-3.31.0-null-pointer-dereference-via-nscodec	Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

24 Sep 2026, 12:16

Type	Values Removed	Values Added
First Time		Freerdp freerdp Freerdp
References	~~() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-ffjr-p229-hpch -~~	() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-ffjr-p229-hpch - Exploit, Mitigation, Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/freerdp-before-3.31.0-null-pointer-dereference-via-nscodec -~~	() https://www.vulncheck.com/advisories/freerdp-before-3.31.0-null-pointer-dereference-via-nscodec - Third Party Advisory
CPE		cpe:2.3:a:freerdp:freerdp::::::::

Information

Published : 2026-09-15 16:17

Updated : 2026-09-24 12:16

NVD link : CVE-2026-91954

Mitre link : CVE-2026-91954

CVE.ORG link : CVE-2026-91954

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-476

NULL Pointer Dereference

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