Vulnerability record

CVE-2026-21710

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Full record read. Reported values and explicit gaps below come from the tracked record. Tracker snapshot: Aug 8, 2026.

What it is

Reported

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.… Source description excerpt; complete tracked detail loads below.

NVD published: Mar 31, 2026 · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

What is affected

Reported

Microsoft — cbl2 nodejs18 18.20.3-12. Product-level identification only; no affected-version conclusion is available from this field.

NVD published: Mar 31, 2026 · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

Urgency and basis

Reported

Track* · 229.5

Tracker decision tier from the evidence detailed below · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

Exploitation evidence

Not reported

Not reported by tracked sources.

What to do

Reported

A source remediation link is available. Validate that guidance against the affected product and your environment.

Source remediation ↗

Tracked source remediation field · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

Evidence detail

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