Name: CVE-2026-23533: Heap-based Buffer Overflow
Creator: Rapid7
Published: 2026-01-19T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-23533, CWE-122, CVSS 9.8, EPSS 0.00533

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.

CVSS Details

CVSS 4.0 Base Score: 7.7 (HIGH)
CVSS 4.0 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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X)
CVSS 3.1 Base Score: 9.8
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alma_linux	—	Upgrade freerdp-libsUpgrade libwinprUpgrade libwinpr-develUpgrade freerdp-develUpgrade freerdp	Feb 9, 2026	Feb 5, 2026
Alpine Linux	—	Upgrade freerdp	Feb 10, 2026	Jan 19, 2026
Amazon Linux Ami 2	—	Upgrade libwinpr-develUpgrade freerdpUpgrade libwinprUpgrade freerdp-debuginfoUpgrade freerdp-develUpgrade freerdp-libs	May 20, 2026	May 20, 2026
Amazon_linux_2023	—	Upgrade freerdp-serverUpgrade freerdp-server-debuginfoUpgrade freerdp-libs-debuginfoUpgrade libwinprUpgrade libwinpr-debuginfoUpgrade freerdp-develUpgrade freerdp-libsUpgrade freerdp-debuginfoUpgrade libwinpr-develUpgrade freerdpUpgrade freerdp-debugsource	Feb 10, 2026	Jan 19, 2026
Debian	—	Upgrade freerdp3	Jul 23, 2026	Jul 23, 2026
Oracle_linux	—	Upgrade freerdp-serverUpgrade libwinpr-develUpgrade freerdp-libsUpgrade libwinprUpgrade freerdp-develUpgrade freerdp	Feb 9, 2026	Jan 19, 2026
Redhat_linux	—	Upgrade freerdp-serverUpgrade libwinpr-debuginfoUpgrade freerdp-debuginfoUpgrade freerdp-debugsourceUpgrade freerdp-libs-debuginfoUpgrade freerdp-libsNo solution existsUpgrade libwinprUpgrade freerdpUpgrade freerdp-develUpgrade libwinpr-develUpgrade freerdp-server-debuginfo	Feb 10, 2026	Jan 19, 2026
Rocky_linux	—	Upgrade libwinpr-debuginfoUpgrade freerdp-serverUpgrade freerdp-server-debuginfoUpgrade libwinprUpgrade libwinpr-develUpgrade freerdp-develUpgrade freerdp-libsUpgrade freerdpUpgrade freerdp-debuginfoUpgrade freerdp-libs-debuginfoUpgrade freerdp-debugsource	Feb 9, 2026	Feb 6, 2026
Suse	—	Upgrade libwinpr3-3Upgrade freerdp-proxy-pluginsUpgrade winpr-develUpgrade freerdp-serverUpgrade libfreerdp3-3Upgrade freerdp-proxyUpgrade libfreerdp-server-proxy3-3Upgrade freerdpUpgrade freerdp-sdlUpgrade librdtk0-0Upgrade freerdp-devel	Feb 2, 2026	Jan 30, 2026
Ubuntu	—	Upgrade libfreerdp2-2Upgrade libfreerdp3-3Upgrade libfreerdp2-2 (Ubuntu Pro)Upgrade libfreerdp2-2t64 (Ubuntu Pro)	Feb 4, 2026	Jan 19, 2026

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CVSS Details

Covered by Rapid7

Prioritise with Active Threat Intelligence