Linux Distros Unpatched Vulnerability : CVE-2026-21713

medium Nessus Plugin ID 303615

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.

- A flaw in Node.js HMAC verification uses a non-constant-time comparison when validating user-provided signatures, potentially leaking timing information proportional to the number of matching bytes. Under certain threat models where high-resolution timing measurements are possible, this behavior could be exploited as a timing oracle to infer HMAC values. Node.js already provides timing-safe comparison primitives used elsewhere in the codebase, indicating this is an oversight rather than an intentional design decision. This vulnerability affects **20.x, 22.x, 24.x, and 25.x**. (CVE-2026-21713)

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://access.redhat.com/security/cve/cve-2026-21713

https://security-tracker.debian.org/tracker/CVE-2026-21713

https://ubuntu.com/security/CVE-2026-21713

Plugin Details

Severity: Medium

ID: 303615

File Name: unpatched_CVE_2026_21713.nasl

Version: 1.8

Type: Local

Agent: unix

Family: Misc.

Published: 3/25/2026

Updated: 4/13/2026

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

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.7

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

CVSS Score Source: CVE-2026-21713

CVSS v3

Risk Factor: Medium

Base Score: 5.9

Temporal Score: 5.4

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

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

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:11.0, cpe:/o:canonical:ubuntu_linux:20.04:-:lts, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, p-cpe:/a:centos:centos:nodejs-devel, p-cpe:/a:redhat:enterprise_linux:nodejs-full-i18n, p-cpe:/a:redhat:enterprise_linux:nodejs22, cpe:/o:debian:debian_linux:12.0, p-cpe:/a:debian:debian_linux:nodejs, p-cpe:/a:redhat:enterprise_linux:nodejs-packaging-bundler, p-cpe:/a:centos:centos:nodejs, cpe:/o:canonical:ubuntu_linux:25.10, cpe:/o:redhat:enterprise_linux:9, p-cpe:/a:centos:centos:nodejs-full-i18n, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, p-cpe:/a:centos:centos:v8-13.6-devel, p-cpe:/a:centos:centos:npm, p-cpe:/a:centos:centos:nodejs-npm, p-cpe:/a:centos:centos:v8-12.4-devel, cpe:/o:centos:centos:8, p-cpe:/a:redhat:enterprise_linux:nodejs-packaging, p-cpe:/a:canonical:ubuntu_linux:nodejs, p-cpe:/a:redhat:enterprise_linux:v8-13.6-devel, p-cpe:/a:centos:centos:nodejs-packaging-bundler, cpe:/o:redhat:enterprise_linux:8, cpe:/o:redhat:enterprise_linux:10, cpe:/o:canonical:ubuntu_linux:14.04:-:lts, p-cpe:/a:redhat:enterprise_linux:nodejs-npm, p-cpe:/a:redhat:enterprise_linux:v8-12.4-devel, p-cpe:/a:centos:centos:nodejs-packaging, p-cpe:/a:redhat:enterprise_linux:nodejs-nodemon, p-cpe:/a:redhat:enterprise_linux:nodejs-docs, p-cpe:/a:centos:centos:nodejs-nodemon, p-cpe:/a:redhat:enterprise_linux:nodejs, p-cpe:/a:redhat:enterprise_linux:nodejs-libs, cpe:/o:canonical:ubuntu_linux:16.04:-:lts, p-cpe:/a:centos:centos:nodejs22, p-cpe:/a:redhat:enterprise_linux:npm, p-cpe:/a:redhat:enterprise_linux:nodejs-devel, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, p-cpe:/a:centos:centos:nodejs-docs, p-cpe:/a:centos:centos:nodejs-libs

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: 3/24/2026

Reference Information

CVE: CVE-2026-21713