Description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, FreeRDP's planar bitmap decoder has an out-of-bounds heap write when decoding RLE planar data. In libfreerdp/codec/planar.c, freerdp_bitmap_decompress_planar() validates the X destination coordinate nXDst against the caller-provided destination stride (nDstStep) even when it is writing into the internal temp buffer pTempData. An attacker can bypass the check with a large nDstStep and a large nXDst, causing planar_decompress_plane_rle() to write past the end of pTempData. This vulnerability is fixed in 3.26.0.
Affected products
freerdp: freerdp
References10
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-mpxh-8fq3-x… ExploitMitigationVendor Advisory
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-mpxh-8fq3-x… ExploitMitigationVendor Advisory
- access.redhat.com/errata/RHSA-2026:36203
- access.redhat.com/errata/RHSA-2026:37207
- access.redhat.com/errata/RHSA-2026:38501
- access.redhat.com/errata/RHSA-2026:46383
- access.redhat.com/errata/RHSA-2026:46384
- access.redhat.com/errata/RHSA-2026:46388
- access.redhat.com/errata/RHSA-2026:46389
- access.redhat.com/errata/RHSA-2026:46393
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 4.0
-
7.7
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 6% percentile: 94 · as of 15 November 2026
- CWE
- CWE-787
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