CVE-2026-23884

high

Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.21.0, offscreen bitmap deletion leaves `gdi->drawing` pointing to freed memory, causing UAF when related update packets arrive. A malicious server can trigger a client‑side use after free, 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.

References

https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-cfgj-vc84-f3pp

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

https://github.com/FreeRDP/FreeRDP/blob/3370e30e92a021eb680892dda14d642bc8b8727c/libfreerdp/cache/offscreen.c#L87-L91

https://github.com/FreeRDP/FreeRDP/blob/3370e30e92a021eb680892dda14d642bc8b8727c/libfreerdp/cache/offscreen.c#L114-L122

Details

Source: Mitre, NVD

Published: 2026-01-19

Updated: 2026-01-19

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

Severity: Medium

CVSS v3

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

CVSS v4

Base Score: 8.7

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

Severity: High