CVE-2026-111756: follow-redirects credential header disclosure with array-form headers

CVE-2026-111756 · Severity: high · CVSS 4 · Published 2026-10-20

follow-redirects is a Node.js library that handles HTTP redirects automatically. It is supposed to strip sensitive headers like Authorization and Cookie when redirects cross to a different server, preventing credential theft. However, when array-form headers are used (a valid Node.js feature for controlling header order), the credential stripping silently fails, allowing attackers to harvest victims' credentials through cross-origin redirects. In a protocol downgrade scenario (HTTPS to HTTP), credentials also travel in cleartext.

Technologies: Follow-Redirects, follow-redirects (npm). Vendors: Follow-Redirects, npm.

Quick answers

Is CVE-2026-111756 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-111756 being exploited in the wild.
How severe is CVE-2026-111756?
High severity, with a CVSS score of 4, published 20 October 2026.
Which products and versions are affected?
Follow-Redirects through 1.16.0; follow-redirects (npm) >= 1.16.0, < 1.16.1, SEMVER:introduced=1.16.0,fixed=1.16.1.
Is there a fix for CVE-2026-111756?
Yes. follow-redirects (npm): upgrade to 1.16.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-111756 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-111756?
Check whether you run Follow-Redirects or follow-redirects (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • follow-redirects (npm): upgrade to 1.16.1 or later
    npm install follow-redirects@1.16.1

Technical details

The vulnerability stems from use of for...in iteration over the headers container, which yields numeric indices ("0", "1", "2") when headers are an array rather than object keys. The removeMatchingHeaders function's regex filters never match these numeric indices, so credential headers remain unstripped. This affects three stripping operations: built-in credentials (Authorization, Proxy-Authorization, Cookie), user-declared sensitiveHeaders, and Host header management. An unauthenticated remote attacker can trigger disclosure by responding with a cross-origin redirect to any server the victim contacts.

Affected products

  • follow-redirects follow-redirects through 1.16.0

Identifiers

  • CVE-2026-111756
  • GHSA-q3jh-wrc6-jgq8

Timeline

  • 2026-10-20: disclosed

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