Description
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.27.0, FreeRDP H.264 decoder backends can return YUV planes sized from the bitstream without comparing the decoded width and height to the RDPGFX surface dimensions used to validate region rectangles. A malicious RDP server can provide an AVC420 or AVC444 bitstream whose decoded frame is smaller than the negotiated surface, causing yuv420_context_decode and the YUV-to-RGB conversion paths to read beyond the decoder-owned planes in libfreerdp/codec/h264.c and the selected H.264 backend. This can disclose client memory or crash the client. This issue is fixed in version 3.27.0.
Affected products
freerdp: freerdp
References5
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3mmf-qh4f-f… ExploitMitigationVendor Advisory
- github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3mmf-qh4f-f… ExploitMitigationVendor Advisory
- github.com/FreeRDP/FreeRDP/commit/0cd45b70bb1fe6befd258ff64c464… Patch
- github.com/FreeRDP/FreeRDP/pull/12873 Issue TrackingPatch
- github.com/FreeRDP/FreeRDP/releases/tag/3.27.0 Release Notes
Metrics
- CVSS 3.1
-
8.2
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H - CVSS 4.0
-
7.2
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/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
- 0% percentile: 39 · as of 10 November 2026
- CWE
- CWE-125
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