Medium severity · published Sep 15, 2026
CVE-2026-91954
FreeRDP before 3.31.0 NULL Pointer Dereference via NSCodec
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 33% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRDP · FreeRDP
before 3.31.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-91954
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-91954
Exploit
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-ffjr-p229-hpch
Third Party Advisory
https://www.vulncheck.com/advisories/freerdp-before-3.31.0-null-pointer-dereference-via-nscodec
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