Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 26.04 LTS / Pro Realtime 24.04 LTS : ruby-jwt vulnerability (USN-9059-1)

critical Nessus Plugin ID 381372

Synopsis

The remote Ubuntu host is missing a security update.

Description

The remote Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 26.04 LTS / Pro Realtime 24.04 LTS host has a package installed that is affected by a vulnerability as referenced in the USN-9059-1 advisory.

It was discovered that ruby-jwt incorrectly verified HMAC signatures when the verification key was empty or missing. A remote attacker could possibly use this issue to forge tokens and bypass authentication.

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected ruby-jwt package.

See Also

https://ubuntu.com/security/notices/USN-9059-1

Plugin Details

Severity: Critical

ID: 381372

File Name: ubuntu_USN-9059-1.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 11/14/2026

Updated: 11/14/2026

Supported Sensors: Continuous Assessment, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.3

Percentile: 53.46

CVSS v2

Risk Factor: High

Base Score: 9.4

Temporal Score: 7

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

CVSS Score Source: CVE-2026-45363

CVSS v3

Risk Factor: Critical

Base Score: 9.1

Temporal Score: 7.9

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

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

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, p-cpe:/a:canonical:ubuntu_linux:ruby-jwt

Required KB Items: Host/cpu, Host/Ubuntu, Host/Ubuntu/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 11/11/2026

Vulnerability Publication Date: 5/18/2026

Reference Information

CVE: CVE-2026-45363

USN: 9059-1