Linux Distros Unpatched Vulnerability : CVE-2026-56789

high Nessus Plugin ID 323746

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.

- RTKLIB through 2.4.3 contains a heap buffer overflow vulnerability in the readrnxobsb function in src/rinex.c that allows attackers to trigger memory corruption by failing to clamp satellite count values from RINEX epoch headers. Attackers can craft malicious RINEX files declaring more than 64 satellites per epoch to cause heap buffer overflow writes and out-of-bounds stack reads, crashing RTKLIB-based applications including rnx2rtkp and RTKPOST. (CVE-2026-56789)

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-2026-56789

https://ubuntu.com/security/CVE-2026-56789

Plugin Details

Severity: High

ID: 323746

File Name: unpatched_CVE_2026_56789.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 6/30/2026

Updated: 6/30/2026

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: Low

Score: 3

CVSS v2

Risk Factor: High

Base Score: 9

Temporal Score: 8.1

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

CVSS Score Source: CVE-2026-56789

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7.4

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

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

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:11.0, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, cpe:/o:debian:debian_linux:14.0, p-cpe:/a:debian:debian_linux:rtklib, p-cpe:/a:canonical:ubuntu_linux:rtklib, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, cpe:/o:canonical:ubuntu_linux:25.10, cpe:/o:debian:debian_linux:13.0, cpe:/o:canonical:ubuntu_linux:26.04:-:lts, cpe:/o:canonical:ubuntu_linux:20.04:-:lts, cpe:/o:debian:debian_linux:12.0

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

Exploit Available: true

Exploit Ease: Exploits are available

Vulnerability Publication Date: 6/25/2026

Reference Information

CVE: CVE-2026-56789