CVE-2026-44421

high

Published 2026-05-29 · Modified 2026-06-02

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CVSS v3

8.8

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS v4 NEW

—

not yet in upstream

VIR risk

8.8

Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, a malicious RDP server can trigger a heap-buffer-overflow write in the FreeRDP client by sending crafted RDPGFX PDUs. The bug is in gdi_CacheToSurface: it validates a destination rectangle that is clamped to UINT16_MAX, but then performs the copy using the original cacheEntry->width/height. This can cause a large out-of-bounds heap write and may lead to client crashes or code execution. This bug is reachable from a malicious RDP server, but only when the client has RDPGFX enabled. This vulnerability is fixed in 3.26.0.

Predictions

Exploit likelihood

92%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

Mitigation details

Source: Debian Security Tracker · View original ↗ · DFSG

CVE-2026-44421 NameCVE-2026-44421 DescriptionFreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, a malicious RDP server can trigger a heap-buffer-overflow write in the FreeRDP client by sending crafted RDPGFX PDUs. The bug is in gdi_CacheToSurface: it validates a destination rectangle that is clamped to UINT16_MAX, but then performs the copy using the original…

CVE-2026-44421

Name	CVE-2026-44421
Description	FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.26.0, a malicious RDP server can trigger a heap-buffer-overflow write in the FreeRDP client by sending crafted RDPGFX PDUs. The bug is in gdi_CacheToSurface: it validates a destination rectangle that is clamped to UINT16_MAX, but then performs the copy using the original cacheEntry->width/height. This can cause a large out-of-bounds heap write and may lead to client crashes or code execution. This bug is reachable from a malicious RDP server, but only when the client has RDPGFX enabled. This vulnerability is fixed in 3.26.0.
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+deb13u3	vulnerable
	forky, sid	3.26.0+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)	3.26.0+dfsg-1

Notes

https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff

Home - Debian Security - Source (Git)

Apply commands

text fix

Notes

https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6r2-4hgm-m6ff

OS impact

SUSE Affected 1 release

Version	Status	Fixed in
—	Affected	—

Debian Mixed 5 releases

Version	Status	Fixed in
trixie	Affected	—
sid	Fixed	`3.26.0+dfsg-1`
forky	Fixed	`3.26.0+dfsg-1`
bullseye	Affected	—
bookworm	Affected	—

Application impact

Vendor	Product	Versions	Fixed
freerdp	freerdp	`{"endExcluding":"3.26.0"}`	`3.26.0`

References

CWEs

CWE-122

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.