Detections
Analytics

Linux Distros Unpatched Vulnerability : CVE-2026-121943

medium Nessus Plugin ID 376492

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.

 - Irontec sngrep through 1.9.0 contains an out-of-bounds stack read vulnerability in sip_check_packet and sip_validate_packet caused by an off-by-one length check on 10240-byte SIP payloads. Remote attackers can send a crafted UDP or TCP SIP packet or supply a pcap file to crash sngrep or leak adjacent stack bytes into displayed SIP fields. (CVE-2026-121943)

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-2026-121943

https://ubuntu.com/security/CVE-2026-121943

Plugin Details

Severity: Medium

ID: 376492

File Name: unpatched_CVE_2026_121943.nasl

Version: 1.3

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: 8.38

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.6

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

CVSS Score Source: CVE-2026-121943

CVSS v3

Risk Factor: Medium

Base Score: 4.8

Temporal Score: 4.4

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

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

CVSS v4

Risk Factor: Medium

Base Score: 6.3

Threat Score: 1.7

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/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: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, cpe:/o:debian:debian_linux:14.0, p-cpe:/a:canonical:ubuntu_linux:sngrep, p-cpe:/a:debian:debian_linux:sngrep

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-2026-121943