CVE-2026-21637

CVE Information
CVE ID
CVE-2026-21637
Severity
HIGH CVSS 7.5
Publish Date
2026-01-20
Description

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.

Collection Date
2026-02-05
Impact Summary
Affected Hosts 1
Related Incidents 0
Related Alerts 0
Affected Hosts (1)
Hostname OS Type Severity Total CVEs
DESKTOP-FNUMV3U WINDOWS CRITICAL 200