CVE-2026-21637 Affecting nodejs:20/nodejs-nodemon package, versions <0:3.0.1-1.module_el8.10.0+3982+85c136aa


Severity

Recommended
0.0
high
0
10

Based on AlmaLinux security rating.

Threat Intelligence

EPSS
0.04% (11th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-ALMALINUX8-NODEJS-15281530
  • published14 Feb 2026
  • disclosed17 Feb 2026

Introduced: 14 Feb 2026

NewCVE-2026-21637  (opens in a new tab)

How to fix?

Upgrade AlmaLinux:8 nodejs:20/nodejs-nodemon to version 0:3.0.1-1.module_el8.10.0+3982+85c136aa or higher.
This issue was patched in ALSA-2026:2422.

NVD Description

Note: Versions mentioned in the description apply only to the upstream nodejs:20/nodejs-nodemon package and not the nodejs:20/nodejs-nodemon package as distributed by AlmaLinux. See How to fix? for AlmaLinux:8 relevant fixed versions and status.

A flaw in Node.js TLS error handling allows remote attackers to crash or exhaust resources of a TLS server when pskCallback or ALPNCallback are in use. Synchronous exceptions thrown during these callbacks bypass standard TLS error handling paths (tlsClientError and error), causing either immediate process termination or silent file descriptor leaks that eventually lead to denial of service. Because these callbacks process attacker-controlled input during the TLS handshake, a remote client can repeatedly trigger the issue. This vulnerability affects TLS servers using PSK or ALPN callbacks across Node.js versions where these callbacks throw without being safely wrapped.

CVSS Base Scores

version 3.1