CVE-2025-21620

Severity CVSS v4.0:
Pending analysis
Type:
CWE-200 Information Leak / Disclosure
Publication date:
06/01/2025
Last modified:
15/04/2026

Description

Deno is a JavaScript, TypeScript, and WebAssembly runtime with secure defaults. When you send a request with the Authorization header to one domain, and the response asks to redirect to a different domain, Deno'sfetch() redirect handling creates a follow-up redirect request that keeps the original Authorization header, leaking its content to that second domain. This vulnerability is fixed in 2.1.2.