FKIE_CVE-2026-21637

Vulnerability from fkie_nvd - Published: 2026-01-20 21:16 - Updated: 2026-01-30 20:18
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
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.
References
support@hackerone.comhttps://nodejs.org/en/blog/vulnerability/december-2025-security-releasesRelease Notes, Vendor Advisory
Impacted products
Vendor Product Version
nodejs node.js *
nodejs node.js *
nodejs node.js *
nodejs node.js *
To clipboard 

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      "value": "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."
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      "value": "Una falla en el manejo de errores TLS de Node.js permite a atacantes remotos colapsar o agotar los recursos de un servidor TLS cuando se utilizan \u0027pskCallback\u0027 o \u0027ALPNCallback\u0027. Las excepciones s\u00edncronas lanzadas durante estas devoluciones de llamada eluden las rutas est\u00e1ndar de manejo de errores TLS (tlsClientError y error), causando una terminaci\u00f3n inmediata del proceso o fugas silenciosas de descriptores de archivo que eventualmente conducen a una denegaci\u00f3n de servicio. Debido a que estas devoluciones de llamada procesan entradas controladas por el atacante durante el handshake TLS, un cliente remoto puede desencadenar el problema repetidamente. Esta vulnerabilidad afecta a los servidores TLS que utilizan devoluciones de llamada PSK o ALPN en todas las versiones de Node.js donde estas devoluciones de llamada lanzan excepciones sin ser envueltas de forma segura."
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  "id": "CVE-2026-21637",
  "lastModified": "2026-01-30T20:18:32.377",
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