---
id: "CVE-2026-123874"
page: "https://infrastack.ai/live/CVE-2026-123874"
kind: "vulnerability"
aliases: ["CVE-2026-123874"]
title: "Node.js: HTTP/2 use-after-free lets unauthenticated clients corrupt server memory"
severity: "high"
cvss: 7.5
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["http2", "node.js", "runtime", "self-hosted"]
not_affected_if: ["no-respondwithfile", "older-node-lines"]
published_at: "2026-11-11T19:17:34+00:00"
first_seen_at: "2026-11-11T19:28:45+00:00"
updated_at: "2026-11-11T19:30:07+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-123874", "first_seen_at": "2026-11-11T19:28:45+00:00"}]
exploit_sources: []
---

# Node.js: HTTP/2 use-after-free lets unauthenticated clients corrupt server memory

Link for people: https://infrastack.ai/live/CVE-2026-123874 (this .md is for agents)

A use-after-free in Node.js HTTP/2 lets a client make the server free a stream while a queued write still points to it, then call through the freed object. An unauthenticated attacker can corrupt server memory over TLS or cleartext.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `node --version` and compare against the affected ranges: 26.x from 26.9.0 and 24.x from 24.22.0.
- Search application code for `respondWithFile(` or `respondWithFD(` on HTTP/2 streams.

## Fix

- Node.js 26.x and 24.x lines: upgrade to a release that includes the fix; the exact fixed version is unknown from the sources.

## Timeline

- 2026-11-11T19:28:45+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-123874

## From the sources

A use-after-free in Node.js HTTP/2 lets an unauthenticated client corrupt server memory, over both TLS and cleartext, when the server serves files with respondWithFile() or respondWithFD(). A client can make the server free an Http2Stream while a write request that points to it is still queued on the socket; when that write completes, the code dereferences and makes a virtual call through the freed object. The only precondition is that the application serves a file with stream.respondWithFile() or stream.respondWithFD(), with default settings otherwise. This vulnerability affects Node.js 26.x (since 26.9.0) and 24.x (since 24.22.0).

---

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