CVE-2026-21710

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**

Referanslar

• https://nodejs.org/en/blog/vulnerability/march-2026-security-releases
• https://access.redhat.com/errata/RHSA-2026:7080
• https://access.redhat.com/errata/RHSA-2026:7123
• https://access.redhat.com/errata/RHSA-2026:7302
• https://access.redhat.com/errata/RHSA-2026:7310
• https://access.redhat.com/errata/RHSA-2026:7350