# CVE-2026-126051: Node.js TLS server use-after-destroy in deferred handshake callbacks

Source: https://junglewise.ai/threats/cve-2026-126051-a-deferred-callback-use-after-destroy-in-node-js-tls-server  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-11. Updated: 2026-11-11  
License: CC BY 4.0 with a link back

CVE-2026-126051 · Severity: high · CVSS 7.5 · Published 2026-11-11

Node.js TLS servers that use certain handshake hooks (SNI, OCSP, session management) crash when a remote attacker sends a specially crafted TLS client hello followed by a connection close. An attacker can remotely terminate any affected TLS server process without authentication, causing service outages for applications relying on TLS encryption.

Technologies: [OpenJS Foundation Node.js](https://junglewise.ai/threats/technologies/openjs-foundation-node-js). Vendors: [OpenJS Foundation](https://junglewise.ai/threats/vendors/openjs-foundation).

## Quick answers

**Is CVE-2026-126051 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-126051 being exploited in the wild.

**How severe is CVE-2026-126051?** High severity, with a CVSS score of 7.5, published 11 November 2026.

**Which products and versions are affected?** OpenJS Foundation Node.js 26.x, 24.x.

**Is there a fix for CVE-2026-126051?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-126051 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-126051?** Check whether you run OpenJS Foundation Node.js at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A use-after-destroy flaw in deferred OpenSSL callback handling allows a remote, unauthenticated attacker to trigger an uncaught exception in Node.js TLS servers. When SNICallback, OCSPRequest, newSession, resumeSession hooks, or server.addContext() are used, the corresponding callbacks are deferred; if the underlying socket is destroyed between scheduling and execution, the deferred code attempts to operate on destroyed memory. An attacker sends a client hello that triggers the vulnerable path (e.g., no SNI with OCSP request) followed by padding and a socket FIN, causing OpenSSL to deliver both the client hello and EOF in the same event loop tick, destroying the socket before the callback executes.

## Affected products

- OpenJS Foundation Node.js 26.x, 24.x

## Timeline

- 2026-11-11: disclosed

## References

- [https://cna.openjsf.org/security-advisories.html](https://cna.openjsf.org/security-advisories.html)
- [https://nodejs.org/en/blog/vulnerability/november-2026-security-releases](https://nodejs.org/en/blog/vulnerability/november-2026-security-releases)

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