CVE-2026-33986

FreeRDP: H.264 YUV Buffer Dimension Desync - Heap OOB Write

Published: Mar 30, 2026Updated: Jul 15, 2026 Sources: CVE List NVD BDUCWE-122

7.5HIGH

Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, in yuv_ensure_buffer() in libfreerdp/codec/h264.c, h264->width and h264->height are updated before the reallocation loop. If any winpr_aligned_recalloc() call fails, the function returns FALSE but width/height are already inflated. This issue has been patched in version 3.24.2.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:HAttack Complexity

High

PR:NPrivileges Required

None

UI:RUser Interaction

Required

Scope

S:UScope

Unchanged

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:HAvailability

High

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Weaknesses

CWE-122 CWE-131

Affected Products

oss-project·US

commercial·RUaka ivk

АЛЬТ СП 10On-premOS

Operating Systems / linux-distro

Free Software Foundation, Inc.

oss-project·USaka fsf, free software foundation

FreeRDP

OSS Libraries

and 1 more affected products View all →

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Initial Access

Privilege Escalation

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References

https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-h6qw-wxvm-hf97

github.com

https://github.com/FreeRDP/FreeRDP/commit/f6e43e208958140074ae9bb93cd0c9045a371c77

github.com

https://altsp.su/obnovleniya-bezopasnosti/

altsp.su

and 3 more references View all →

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