CVE-2026-111756
8.2HighPublished 20 Oct 2026 · NVD status: Awaiting Analysis · AI triage by gemini-3.8-flash
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Impact
- High impact on confidentiality
- Weakness
- CWE-200, CWE-212
Impact
Remote servers can steal sensitive credential headers like Authorization, Cookie, and Proxy-Authorization. The attacker just needs the vulnerable application to request a URL that issues a cross-origin redirect to an attacker-controlled endpoint.
Root cause
The header sanitization routine uses a for...in loop assuming headers are an object, which fails to match and drop sensitive keys when headers are provided as an array.
Affected systems
follow-redirects version 1.16.0 to before 1.16.1
CVSS v4.0 · CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Fix & remediation
Upgrade follow-redirects to version 1.16.1 or later. As an interim workaround, pass headers as a standard key-value object instead of an array.
$ npm install follow-redirects@^1.16.1AI-suggested. Run it in staging first and check it against the vendor advisory. Why?
NVD 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.