Vulnerability · Published Nov 3, 2026 · Assigned by VulnCheck

CVE-2026-121396FreeRDP 3.0.0 before 3.32.2 denial of service via RTS padding assertion

Medium 4.3

In plain English

A medium-severity security flaw in FreeRDP from FreeRDP. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.3Medium

Exploit odds (30 days)0.3%top 75.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

FreeRDP clients from 3.0.0 before 3.32.2 built with verbose WinPR assertions contain a reachable assertion in rts_read_auth_verifier triggered by malformed RTS padding. Attackers controlling an RD Gateway can send a crafted RPC-over-HTTP RTS PDU with inconsistent authentication padding to abort the connecting client process.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	freerdp2	no fix listed	DEBIAN-CVE-2026-121396
Debian:13	freerdp3	no fix listed	DEBIAN-CVE-2026-121396
Debian:14	freerdp3	3.32.2+dfsg-1	DEBIAN-CVE-2026-121396
Ubuntu:22.04:LTS	freerdp2	no fix listed	UBUNTU-CVE-2026-121396
Ubuntu:24.04:LTS	freerdp3	no fix listed	UBUNTU-CVE-2026-121396
Ubuntu:26.04:LTS	freerdp3	no fix listed	UBUNTU-CVE-2026-121396
Ubuntu:26.10	freerdp3	no fix listed	UBUNTU-CVE-2026-121396

Affected products (as reported)

Vendor	Product	Versions
FreeRDP	FreeRDP	3.0.0 – before 3.32.2

Weakness: CWE-617 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

References

GitHub Security Advisory (GHSA-6p3w-fv52-cf24) vendor-advisory
VulnCheck Advisory: FreeRDP 3.0.0 before 3.32.2 denial of service via RTS padding assertion third-party-advisory