Microsoft security update for CVE-2026-21710
🔗 CVE IDs covered (1)
📋 Microsoft's advisory
EchelonGraph does not copy Microsoft's advisory page: its FAQ and remediation text are not shown here. Read the advisory on https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21710. This page also shows what EchelonGraph holds for CVE-2026-21710, with the description from its CVE record, which the CVE Numbering Authority that assigned the CVE wrote: for a CVE Microsoft assigned, often in the words of Microsoft's own advisory.
🎯 Affected products7
- Microsoft Visual Studio 2019 version 16.11 (includes 16.0 - 16.10)
- Microsoft Visual Studio 2022 version 17.14
- azl3 nodejs 20.14.0-14 on Azure Linux 3.0
- azl3 nodejs24 24.13.0-3 on Azure Linux 3.0
- cbl2 nodejs18 18.20.3-12
- cbl2 nodejs18 18.20.3-12 on CBL Mariner 2.0
- cbl2 nodejs18 18.20.3-12 on CBL-Mariner 2.0
✅ Updates Microsoft lists: 5 updates
5 rows: one per KB article or update, update type and fixed build. Their details are on Microsoft's advisory.
| KB article | Update | Fixed build |
|---|---|---|
| — | Security Update | 20.14.0-15 |
| — | Security Update | 24.14.1-1 |
| — | Security Update | 16.11.59 |
| — | Security Update | 17.14.38 |
| — | Security Update | — |
🧭 EchelonGraph on CVE-2026-21710
- EchelonGraph score
- 7.5 HIGH
- CISA KEV
- Not listed
- Fix status
- A fix is available — apply it.
Description from the CVE record (CVE.org), as published by its numbering authority
A flaw in Node.js HTTP request handling causes an uncaught `TypeError` when a request is received with a header named `__proto__` and the application accesses `req.headersDistinct`. When this occurs, `dest["__proto__"]` resolves to `Object.prototype` rather than `undefined`, causing `.push()` to be called on a non-array. This exception is thrown synchronously inside a property getter and cannot be intercepted by `error` event listeners, meaning it cannot be handled without wrapping every `req.headersDistinct` access in a `try/catch`. * This vulnerability affects all Node.js HTTP servers on **20.x, 22.x, 24.x, and v25.x**
Published by HackerOne, the CVE Numbering Authority that assigned CVE-2026-21710, in its CVE record at CVE.org; reused under the CVE Program's Terms of Use (its licence and MITRE's copyright notice are in our Terms of Service).