Linux Distros Unpatched Vulnerability : CVE-2026-91953

high Nessus Plugin ID 346011

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 versions before 3.31.0 contain a heap buffer overflow vulnerability in nego_send_negotiation_request() that fails to validate the LB_LOAD_BALANCE_INFO field length before writing to a fixed 512-byte buffer. A malicious RDP server or man-in-the-middle can send a Server Redirection PDU with an oversized LB_LOAD_BALANCE_INFO value to overflow the buffer with attacker- controlled content, causing denial of service or heap corruption before authentication completes.
(CVE-2026-91953)

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://access.redhat.com/security/cve/cve-2026-91953

https://security-tracker.debian.org/tracker/CVE-2026-91953

https://ubuntu.com/security/CVE-2026-91953

Plugin Details

Severity: High

ID: 346011

File Name: unpatched_CVE_2026_91953.nasl

Version: 1.9

Type: Local

Agent: unix

Family: Misc.

Published: 9/15/2026

Updated: 10/6/2026

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: 23.62

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 7

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

CVSS Score Source: CVE-2026-91953

CVSS v3

Risk Factor: Medium

Base Score: 6.5

Temporal Score: 6.2

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

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

CVSS v4

Risk Factor: High

Base Score: 7.1

Threat Score: 5.7

Threat Vector: CVSS:4.0/E:P

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

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:16.04:-:lts, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, cpe:/o:canonical:ubuntu_linux:20.04:-:lts, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, cpe:/o:centos:centos:7, cpe:/o:centos:centos:8, cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0, cpe:/o:redhat:enterprise_linux:7, cpe:/o:redhat:enterprise_linux:8, cpe:/o:redhat:enterprise_linux:9, p-cpe:/a:canonical:ubuntu_linux:freerdp2, p-cpe:/a:canonical:ubuntu_linux:freerdp, p-cpe:/a:centos:centos:freerdp-devel, p-cpe:/a:centos:centos:freerdp-libs, p-cpe:/a:centos:centos:freerdp-plugins, p-cpe:/a:centos:centos:freerdp, p-cpe:/a:centos:centos:libwinpr-devel, p-cpe:/a:centos:centos:libwinpr, p-cpe:/a:debian:debian_linux:freerdp2, p-cpe:/a:debian:debian_linux:freerdp3, p-cpe:/a:redhat:enterprise_linux:freerdp-devel, p-cpe:/a:redhat:enterprise_linux:freerdp-libs, p-cpe:/a:redhat:enterprise_linux:freerdp-plugins, p-cpe:/a:redhat:enterprise_linux:freerdp, p-cpe:/a:redhat:enterprise_linux:libwinpr-devel, p-cpe:/a:redhat:enterprise_linux:libwinpr

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

Exploit Available: true

Exploit Ease: Exploits are available

Vulnerability Publication Date: 9/15/2026

Reference Information

CVE: CVE-2026-91953