Detections
Analytics

Linux Distros Unpatched Vulnerability : CVE-2026-121550

low Nessus Plugin ID 376535

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.

 - nnn through 5.3 contains an insecure file handling vulnerability that allows local attackers to redirect writes because main() accepts an existing NNN_FIFO path without verifying it is a FIFO. Attackers can pre- create the documented predictable /tmp/nnn.fifo path as a symlink or readable regular file, causing victim-writable files to be overwritten or leaking the victim's browsed paths. (CVE-2026-121550)

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://ubuntu.com/security/CVE-2026-121550

Plugin Details

Severity: Low

ID: 376535

File Name: unpatched_CVE_2026_121550.nasl

Version: 1.2

Type: Local

Agent: unix

Family: Misc.

Published: 11/5/2026

Updated: 11/6/2026

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: 2.1

Percentile: 8.32

CVSS v2

Risk Factor: Low

Base Score: 2.4

Temporal Score: 2

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

CVSS Score Source: CVE-2026-121550

CVSS v3

Risk Factor: Low

Base Score: 3.3

Temporal Score: 3.1

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

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

CVSS v4

Risk Factor: Low

Base Score: 1

Threat Score: 0.1

Threat Vector: CVSS:4.0/E:U

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

Vulnerability Information

CPE: 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, p-cpe:/a:canonical:ubuntu_linux:nnn

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: 11/3/2026

Reference Information

CVE: CVE-2026-121550