CVE-2026-23530

EUVD-2026-3311

19.01.2026, 17:15

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0,`freerdp_bitmap_decompress_planar` does not validate `nSrcWidth`/`nSrcHeight` against `planar->maxWidth`/`maxHeight` before RLE decode. 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.

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	Primary	9.8 CRITICAL	NETWORK	LOW	NONE	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Base Score

CVSS 3.x

EPSS Score

Percentile: 35%

Affected Products (NVD)

Vendor	Product	Version
freerdp	freerdp	𝑥 < 3.21.0

𝑥

= Vulnerable software versions

Debian Releases

Debian Product

Codename

freerdp2

bookworm	no-dsa
bullseye	vulnerable
bullseye (security)	vulnerable
trixie	no-dsa

freerdp3

bookworm	no-dsa
forky	3.23.0+dfsg-1 fixed
sid	3.23.0+dfsg-1 fixed
trixie	no-dsa

Known Exploits!

https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-r4hv-852m-fq7p

Common Weakness Enumeration

CWE-122 - Heap-based Buffer Overflow
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

Vulnerability Media Exposure

[GERMAN] FreeRDP: Mehrere Schwachstellen ermöglichen DoS und Codeausführung
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in FreeRDP ausnutzen, um einen Denial-of-Service-Zustand zu verursachen oder möglicherweise beliebigen Code auszuführen.
Published: 2026-01-19T23:00:00+00:00

References

https://github.com/FreeRDP/FreeRDP/blob/38514dfa5813aa945a86cfbcec279033f8394468/libfreerdp/codec/planar.c#L1689-L1696

https://github.com/FreeRDP/FreeRDP/blob/38514dfa5813aa945a86cfbcec279033f8394468/libfreerdp/codec/planar.c#L1713-L1716

https://github.com/FreeRDP/FreeRDP/blob/38514dfa5813aa945a86cfbcec279033f8394468/libfreerdp/codec/planar.c#L951-L953

https://github.com/FreeRDP/FreeRDP/releases/tag/3.21.0

https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-r4hv-852m-fq7p