Linux Distros Unpatched Vulnerability : CVE-2026-27889

high Nessus Plugin ID 303826

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.

- NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Starting in version 2.2.0 and prior to versions 2.11.14 and 2.12.5, a missing sanity check on a WebSockets frame could trigger a server panic in the nats-server. This happens before authentication, and so is exposed to anyone who can connect to the websockets port. Versions 2.11.14 and 2.12.5 contains a fix. A workaround is available. The vulnerability only affects deployments which use WebSockets and which expose the network port to untrusted end-points. If one is able to do so, a defense in depth of restricting either of these will mitigate the attack. (CVE-2026-27889)

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-2026-27889

Plugin Details

Severity: High

ID: 303826

File Name: unpatched_CVE_2026_27889.nasl

Version: 1.1

Type: local

Agent: unix

Family: Misc.

Published: 3/26/2026

Updated: 3/26/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: High

Base Score: 9.4

Temporal Score: 8

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

CVSS Score Source: CVE-2026-27889

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.9

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

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

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:14.0, cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0, p-cpe:/a:debian:debian_linux:nats-server

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: 3/25/2026

Reference Information

CVE: CVE-2026-27889