Linux Distros Unpatched Vulnerability : CVE-2026-121963

high Nessus Plugin ID 376216

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- FreeRDP before 3.32.2 contains a use-after-free vulnerability in the asynchronous dynamic rdpsnd channel that allows malicious RDP servers to trigger freed callback access by closing the channel with queued audio PDUs. Attackers can send a training PDU then close the channel so the playback thread reads the freed callback in rdpsnd_virtual_channel_write, crashing the client. (CVE-2026-121963)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://security-tracker.debian.org/tracker/CVE-2026-121963

https://ubuntu.com/security/CVE-2026-121963

Plugin Details

Severity: High

ID: 376216

File Name: unpatched_CVE_2026_121963.nasl

Version: 1.2

Type: Local

Agent: unix

Family: Misc.

Published: 11/5/2026

Updated: 11/5/2026

Supported Sensors: Agentless Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.81

CVSS v3

Risk Factor: Medium

Base Score: 5.9

Temporal Score: 5.6

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:P/RL:U/RC:C

CVSS Score Source: CVE-2026-121963

CVSS v4

Risk Factor: High

Base Score: 8.2

Threat Score: 6.9

Threat Vector: CVSS:4.0/E:P

Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS Score Source: CVE-2026-121963

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:16.04:-:lts, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0, p-cpe:/a:canonical:ubuntu_linux:freerdp, p-cpe:/a:debian:debian_linux:freerdp2, p-cpe:/a:debian:debian_linux:freerdp3

Required KB Items: Host/cpu, Host/local_checks_enabled, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 11/4/2026

Reference Information

CVE: CVE-2026-121963