Out-of-bounds Write Affecting freerdp package, versions <3.23.0-r0


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.04% (13th percentile)

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  • Snyk IDSNYK-ALPINE323-FREERDP-15364916
  • published28 Feb 2026
  • disclosed25 Feb 2026

Introduced: 25 Feb 2026

NewCVE-2026-26965  (opens in a new tab)
CWE-787  (opens in a new tab)

How to fix?

Upgrade Alpine:3.23 freerdp to version 3.23.0-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream freerdp package and not the freerdp package as distributed by Alpine. See How to fix? for Alpine:3.23 relevant fixed versions and status.

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, in the RLE planar decode path, planar_decompress_plane_rle() writes into pDstData at ((nYDst+y) * nDstStep) + (4*nXDst) + nChannel without verifying that (nYDst+nSrcHeight) fits in the destination height or that (nXDst+nSrcWidth) fits in the destination stride. When TempFormat != DstFormat, pDstData becomes planar-&gt;pTempData (sized for the desktop), while nYDst is only validated against the surface by is_within_surface(). A malicious RDP server can exploit this to perform a heap out-of-bounds write with attacker-controlled offset and pixel data on any connecting FreeRDP client. The OOB write reaches up to 132,096 bytes past the temp buffer end, and on the brk heap (desktop ≤ 128×128), an adjacent NSC_CONTEXT struct's decode function pointer is overwritten with attacker-controlled pixel data — control-flow–relevant corruption (function pointer overwritten) demonstrated under deterministic heap layout (nsc-&gt;decode = 0xFF414141FF414141). Version 3.23.0 fixes the vulnerability.

CVSS Base Scores

version 3.1