Medium [CVE-2026-69159] Out-of-bounds read leads to denial of service and information disclosure

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.29.0, planar_decompress_plane_rle and planar_decompress_plane_rle_only in libfreerdp/codec/planar.c verify that a control byte exists but do not verify that the source buffer contains the zero to fifteen raw bytes declared by that control byte.

A malicious RDP server can send a truncated planar bitmap or surface update whose final control byte claims additional raw bytes, causing the decoder to read beyond pSrcData while processing a color plane. This can crash the client and may disclose adjacent memory.

This issue is fixed in version 3.29.0. This causes the client's decoder to read beyond its allocated buffer, which can lead to a client crash, resulting in a denial of service.

Additionally, this flaw may disclose sensitive information from adjacent memory. An out-of-bounds read vulnerability was found in FreeRDP's planar bitmap decoder (`libfreerdp/codec/planar.c`).

This can lead to a client application crash or partial disclosure of adjacent client memory. Red Hat severity: Moderate — CVSS 5.4 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L).

Weakness: CWE-125. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 10.0 Extended Update Support; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9.