Detections
Analytics

Linux Distros Unpatched Vulnerability : CVE-2026-25537

medium Nessus Plugin ID 298172

Language:

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.

 - jsonwebtoken is a JWT lib in rust. Prior to version 10.3.0, there is a Type Confusion vulnerability in jsonwebtoken, specifically, in its claim validation logic. When a standard claim (such as nbf or exp) is provided with an incorrect JSON type (Like a String instead of a Number), the library's internal parsing mechanism marks the claim as FailedToParse. Crucially, the validation logic treats this FailedToParse state identically to NotPresent. This means that if a check is enabled (like: validate_nbf = true), but the claim is not explicitly marked as required in required_spec_claims, the library will skip the validation check entirely for the malformed claim, treating it as if it were not there. This allows attackers to bypass critical time-based security restrictions (like Not Before checks) and commit potential authentication and authorization bypasses. This issue has been patched in version 10.3.0.
 (CVE-2026-25537)

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-2026-25537

https://ubuntu.com/security/CVE-2026-25537

Plugin Details

Severity: Medium

ID: 298172

File Name: unpatched_CVE_2026_25537.nasl

Version: 1.5

Type: local

Agent: unix

Family: Misc.

Published: 2/5/2026

Updated: 2/16/2026

Supported Sensors: Agentless Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 7

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

CVSS Score Source: CVE-2026-25537

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 7.1

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

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

CVSS v4

Risk Factor: Medium

Base Score: 6.9

Threat Score: 5.5

Threat Vector: CVSS:4.0/E:P

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

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:25.10, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, p-cpe:/a:debian:debian_linux:rust-jsonwebtoken, cpe:/o:debian:debian_linux:14.0, p-cpe:/a:canonical:ubuntu_linux:rust-jsonwebtoken, cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0

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

Exploit Available: true

Exploit Ease: Exploits are available

Vulnerability Publication Date: 2/3/2026

Reference Information

CVE: CVE-2026-25537