[ CVE-2026-111756 · Published 20 Oct 2026 ]
follow-redirects array-form headers bypass cross-origin credential stripping
[ Description ]Official description
follow-redirects is a Node.js HTTP and HTTPS client wrapper that automatically follows redirects. From version 1.16.0 to before version 1.16.1, follow-redirects removes sensitive credential headers (Authorization, Proxy-Authorization, Cookie, and any caller-declared sensitiveHeaders) before following a redirect that crosses to a different host or downgrades to a less secure protocol. The removal routine iterates the caller's headers container with for...in and matches header names against a filter. This assumes the headers container is a plain object keyed by header names. Node's underlying http.request, which follow-redirects is a drop-in replacement for, also accepts headers as an alternating array of names and values. For an array, for...in yields the numeric indices "0", "1", "2" and so on, which never match a header-name filter, so nothing is removed. An application that sends array-form headers and follows an attacker-controlled cross-origin redirect therefore forwards its Authorization, Cookie, and Proxy-Authorization headers verbatim to the attacker-controlled destination, with no error or warning. The sensitiveHeaders option added to fix CVE-2026-40895 / GHSA-r4q5-vmmm-2653 is equally ineffective, because it relies on the same helper. This is an unauthenticated confidentiality vulnerability: any remote server the victim application contacts can harvest the victim's credential headers by responding with a cross-origin redirect. This issue has been patched in version 1.16.1.
[ Fixes ]Fixes and patches
- follow-redirects 1.16.1Fixed version · GitHub Advisories · npm package follow-redirects: upgrade to 1.16.1 or later (affected >= 1.16.0, < 1.16.1)
[ Packages ]Affected open-source packages
- follow-redirects npmAffected >= 1.16.0, < 1.16.1 · fixed in 1.16.1 · GHSA-q3jh-wrc6-jgq8