Linux Distros Unpatched Vulnerability : CVE-2026-93858

high Nessus Plugin ID 364399

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.

- In OpenStack Mistral through 23.0.0, the std.ssh_proxied action passes a caller-supplied proxy_command value directly to paramiko.ProxyCommand() before any SSH connection to a gateway or target host is attempted. An authenticated project member can use the standard action-execution API to submit an arbitrary local command as proxy_command; paramiko starts that command as a subprocess on the executor host under the executor's own service account, independent of whether the SSH connection itself ever succeeds. Only Mistral deployments that permit the std.ssh_proxied action, the default configuration, are affected. (CVE-2026-93858)

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-2026-93858

https://ubuntu.com/security/CVE-2026-93858

Plugin Details

Severity: High

ID: 364399

File Name: unpatched_CVE_2026_93858.nasl

Version: 1.4

Type: Local

Agent: unix

Family: Misc.

Published: 10/9/2026

Updated: 10/30/2026

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

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.38

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2026-93858

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7.1

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

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

CVSS v4

Risk Factor: High

Base Score: 8.7

Threat Score: 6.3

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:L/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:canonical:ubuntu_linux:26.04:-:lts, cpe:/o:canonical:ubuntu_linux:26.10, cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0, p-cpe:/a:canonical:ubuntu_linux:mistral, p-cpe:/a:debian:debian_linux:mistral

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

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 10/8/2026

Reference Information

CVE: CVE-2026-93858