Use-after-free in FreeRDP - #VU164453
Published: November 10, 2026
Vulnerability identifier: #VU164453
CSH Severity: Low
CVSS v4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-416
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to trigger invalid server certificate signatures that can cause validating clients to reject connections.
The vulnerability exists due to use-after-free in FreeRDP's cert_write_server_certificate_v1() when stream reallocation invalidates a saved pointer before signature hashing. A remote attacker can negotiate Standard RDP Security with at least four static channels against a server using a 3072-bit key, or with any channel count against a server using a 4096-bit key, to trigger freed-memory reads and invalid certificate signatures.
Affected software
FreeRDP
Remediation
Install security update from vendor's website.
FreeRDP - update to 3.33.0