High severity · published Jan 14, 2026
CVE-2026-22856
FreeRDP is a free implementation of the Remote Desktop Protocol
8.1
CVSS
0.3%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 26% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
Freerdp · Freerdp
before 3.20.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-22856
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-22856
Release Notes
https://github.com/FreeRDP/FreeRDP/releases/tag/3.20.1
Exploit
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-w842-c386-fxhv
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