CVE-2026-23533

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 RDPGFX ClearCodec decode path when maliciously crafted residual data causes out-of-bounds writes during color output. 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.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
freerdp	26.10 stonking	Not in release
	26.04 LTS resolute	Not in release
	25.10 questing	Not in release
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Not in release
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation
freerdp2	26.10 stonking	Not in release
	26.04 LTS resolute	Not in release
	25.10 questing	Not in release
	24.04 LTS noble	Fixed in 2.11.5+dfsg1-1ubuntu0.1~esm3
	22.04 LTS jammy	Fixed in 2.6.1+dfsg1-3ubuntu2.8
	20.04 LTS focal	Fixed in 2.6.1+dfsg1-0ubuntu0.20.04.2+esm1
	18.04 LTS bionic	Fixed in 2.2.0+dfsg1-0ubuntu0.18.04.4+esm3
freerdp3	26.10 stonking	Not affected
	26.04 LTS resolute	Not affected
	25.10 questing	Fixed in 3.16.0+dfsg-2ubuntu0.3
	24.04 LTS noble	Fixed in 3.5.1+dfsg1-0ubuntu1.4
	22.04 LTS jammy	Not in release

Get expanded security coverage with Ubuntu Pro

Reduce your average CVE exposure time from 98 days to 1 day with expanded CVE patching, ten-years security maintenance and optional support for the full stack of open-source applications. Free for personal use.

Get Ubuntu Pro 30-day free trial

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
freerdp	Upstream: c439182
freerdp2	Upstream: c439182
freerdp3	Upstream: c439182

Severity score breakdown

CVSS version:

Base score 7.7 · High

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Attack requirements	None
Privileges required	None
User interaction	None
Vulnerable system - Confidentiality impact	None
Vulnerable system - Integrity impact	None
Vulnerable system - Availability impact	High
Subsequent system - Confidentiality impact	None
Subsequent system - Integrity impact	None
Subsequent system - Availability impact	None

Scores

Parameter	Value
Base score	7.7 · High
Base + Threat score	-
Base + Environmental score	-
Base + Threat + Environmental score	-

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P

Base score 7.6 · High

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	Required
Scope	Unchanged
Confidentiality impact	Low
Integrity impact	Low
Availability impact	High

Scores

Parameter	Value
Base score	7.6 · High
Exploitability score	-
Impact score	-

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

References

Related Ubuntu Security Notices (USN)

USN-8004-1
FreeRDP vulnerabilities
3 February 2026

USN-8004-2
FreeRDP regression
8 February 2026

USN-8105-1
FreeRDP vulnerabilities
18 March 2026