CVE-2026-109251

FreeRDP before 3.32.0 stores the server-supplied signed MS-RDPEGT geometry origin unchecked in an unsigned video surface coordinate, so the blit clamp in gdiVideoShowSurface() wraps in 32-bit arithmetic and is skipped. A malicious RDP server can send a negative topLevelLeft to clients connecting with /video, causing an out-of-bounds write of decoded H.264 picture data or a client abort.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

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-grvc-qhhp-7h6m
https://www.vulncheck.com/advisories/freerdp-before-3.32.0-out-of-bounds-write-via-ms-rdpegt-video-geometry
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-grvc-qhhp-7h6m

Configurations

No configuration.

History

18 Oct 2026, 12:17

Type	Values Removed	Values Added
References	~~() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-grvc-qhhp-7h6m -~~	() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-grvc-qhhp-7h6m -

12 Oct 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-12 17:17

Updated : 2026-10-18 12:17

NVD link : CVE-2026-109251

Mitre link : CVE-2026-109251

CVE.ORG link : CVE-2026-109251

JSON object : View

Products Affected

No product.

CWE

CWE-129

Improper Validation of Array Index

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