CVE-2026-21637 Affecting nodejs-23 package, versions *


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.04% (14th percentile)

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  • Snyk IDSNYK-MINIMOSLATEST-NODEJS23-15199914
  • published4 Feb 2026
  • disclosed20 Jan 2026

Introduced: 20 Jan 2026

CVE-2026-21637  (opens in a new tab)

How to fix?

There is no fixed version for Minimos:latest nodejs-23.

NVD Description

Note: Versions mentioned in the description apply only to the upstream nodejs-23 package and not the nodejs-23 package as distributed by Minimos. See How to fix? for Minimos:latest 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