What is CVE-2026-22856?

CVE-2026-22856 is a high-severity vulnerability in Freerdp, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 8.1/10. Published 2026-01-14.

How severe is CVE-2026-22856?

High severity. CVSS v3 base score is 8.1 out of 10.

Use After Free in Freerdp

CVE-2026-22856

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.20.1, a race in the serial channel IRP thread tracking allows a heap use‑after‑free when one thread removes an entry from serial->IrpThreads while another reads it. This vulnerability is fixed in 3.20.1.

Vulnerability class: Race Condition

Published 2026-01-14 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.003 (22.9th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 23rd percentile — 22.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000

Affected products

Freerdp — versions < 3.20.1

Weakness classification (CWE)

References

github.com/FreeRDP/FreeRDP/security/advisories/GHSA-w842-c386-fxhv (Exploit, Patch, Vendor Advisory)
github.com/FreeRDP/FreeRDP/releases/tag/3.20.1 (Release Notes)

Frequently asked questions

What is CVE-2026-22856?: CVE-2026-22856 is a high-severity vulnerability in Freerdp, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 8.1/10. Published 2026-01-14.
How severe is CVE-2026-22856?: High severity. CVSS v3 base score is 8.1 out of 10.