CVE-2026-21637
Unknown
Unknown - Not Provided
BaseFortify
Publication date: 2026-01-20
Last updated on: 2026-01-30
Assigner: HackerOne
Description
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.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| nodejs | node.js | From 4.0.0 (inc) to 20.20.0 (exc) |
| nodejs | node.js | From 22.0.0 (inc) to 22.22.0 (exc) |
| nodejs | node.js | From 24.0.0 (inc) to 24.13.0 (exc) |
| nodejs | node.js | From 25.0.0 (inc) to 25.3.0 (exc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-400 | The product does not properly control the allocation and maintenance of a limited resource. |
