Linux Distros Unpatched Vulnerability : CVE-2026-8833

high Nessus Plugin ID 320319

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.

- Improper neutralization of HTML-encoded characters in the URL validation function in Checkmk <2.5.0p5, <2.4.0p31, <2.3.0p48, and all 2.2.0 versions allows an authenticated user to bypass URL validation and inject malicious URLs such as javascript: URIs, resulting in cross-site scripting when another user interacts with the crafted link. (CVE-2026-8833)

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-2026-8833

Plugin Details

Severity: High

ID: 320319

File Name: unpatched_CVE_2026_8833.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 6/10/2026

Updated: 6/10/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.8

CVSS v2

Risk Factor: Low

Base Score: 3.5

Temporal Score: 3

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

CVSS Score Source: CVE-2026-8833

CVSS v3

Risk Factor: Medium

Base Score: 5.4

Temporal Score: 5

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

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

CVSS v4

Risk Factor: High

Base Score: 8.5

Threat Score: 5.9

Threat Vector: CVSS:4.0/E:U

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

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:check-mk, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, cpe:/o:canonical:ubuntu_linux:16.04:-:lts

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: 6/8/2026

Reference Information

CVE: CVE-2026-8833