CVE-2026-55191

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, FreeRDP clients that negotiate RDPGFX AVC444 with an H.264 decoder backend calculate the intermediate YUV444 allocation size in libfreerdp/codec/h264.c with 32-bit multiplication in avc444_ensure_buffer. A malicious RDP server can supply surface dimensions for which piDstStride multiplied by padDstHeight wraps to a small nonzero value, causing winpr_aligned_recalloc to allocate an undersized buffer before YUV420CombineToYUV444 writes using the actual stride and rectangle dimensions. This can cause a client crash and may permit code execution through attacker-influenced heap corruption. This issue is fixed in version 3.27.0.

CVSS

No CVSS.

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/commit/97f40b9e766af375f4e41ac6a3f4397d708d249c
https://github.com/FreeRDP/FreeRDP/pull/12873
https://github.com/FreeRDP/FreeRDP/releases/tag/3.27.0
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vx73-w5q6-7jqr
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vx73-w5q6-7jqr

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 18:16

Updated : 2026-09-09 21:19

NVD link : CVE-2026-55191

Mitre link : CVE-2026-55191

CVE.ORG link : CVE-2026-55191

JSON object : View

Products Affected

No product.

CWE

CWE-122

Heap-based Buffer Overflow

CWE-190

Integer Overflow or Wraparound

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