CVE-2026-23534

Name	CVE-2026-23534
Description	FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, a client-side heap buffer overflow occurs in the ClearCodec bands decode path when crafted band coordinates allow writes past the end of the destination surface buffer. A malicious server can trigger a client‑side heap buffer overflow, causing a crash (DoS) and potential heap corruption with code‑execution risk depending on allocator behavior and surrounding heap layout. Version 3.21.0 contains a patch for the issue.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
freerdp2 (PTS)	bullseye	2.3.0+dfsg1-2+deb11u1	vulnerable
	bullseye (security)	2.3.0+dfsg1-2+deb11u3	vulnerable
	bookworm	2.11.7+dfsg1-6~deb12u1	vulnerable
freerdp3 (PTS)	trixie	3.15.0+dfsg-2.1	vulnerable
	forky, sid	3.22.0+dfsg-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
freerdp2	source	(unstable)	(unfixed)
freerdp3	source	(unstable)	3.21.0+dfsg-1

Notes

[trixie] - freerdp3 <no-dsa> (Minor issue)
[bookworm] - freerdp2 <no-dsa> (Minor issue)
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3frr-mp8w-4599