CVE-2026-40895 MEDIUM

CVE-2026-40895: follow-redirects: Custom Authentication Headers Leaked to Cross-Domain Redirect Targets

Vendor Follow-Redirects
Product follow-redirects
Weakness CWE-200 · Info exposure
Published April 21, 2026
Last update June 30, 2026

CVSS base score

6.9/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

What the vulnerability does

01Description

follow-redirects is an open source, drop-in replacement for Node's `http` and `https` modules that automatically follows redirects. Prior to 1.16.0, when an HTTP request follows a cross-domain redirect (301/302/307/308), follow-redirects only strips authorization, proxy-authorization, and cookie headers (matched by regex at index.js). Any custom authentication header (e.g., X-API-Key, X-Auth-Token, Api-Key, Token) is forwarded verbatim to the redirect target. This vulnerability is fixed in 1.16.0.

Key dates

02Disclosure timeline

April 21, 2026 CVE published
June 30, 2026 Record updated