Double free in FreeRDP - CVE-2026-121956
Published: November 10, 2026 / Updated: November 11, 2026
Vulnerability identifier: #VU164432
CSH Severity: Medium
CVSS v4: 8.7 [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]
CVE-ID: CVE-2026-121956
CWE-ID: CWE-415
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service by crashing the server process.
The vulnerability exists due to double free of shared default-realm storage in FreeRDP's WinPR Kerberos SSPI retrieveSomeTgt function when processing empty-realm principals. A remote attacker can send a pre-authentication NLA/CredSSP u2u token containing server-name "host@" to trigger heap corruption and crash servers with Kerberos enabled, a configured keytab, a valid u2u sub-mechanism, and a configured default realm.
Affected software
FreeRDP
How to mitigate CVE-2026-121956
Install security update from vendor's website.
FreeRDP - update to 3.32.2