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.
Affected: npm: follow-redirects
## Summary
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:469-476). Any custom authentication header (e.g., `X-API-Key`, `X-Auth-Token`, `Api-Key`, `Token`) is forwarded verbatim to the redirect target.
Since `follow-redirects` is the redirect-handling dependency for **axios** (105K+ stars), this vulnerability affects the entire axios ecosystem.
## Affected Code
`index.js`, lines 469-476:
```javascript if (redirectUrl.protocol !== currentUrlParts.protocol && redirectUrl.protocol !== "https:" || redirectUrl.host !== currentHost && !isSubdomain(redirectUrl.host, currentHost)) { removeMatchingHeaders(/^(?:(?:proxy-)?authorization|cookie)$/i, this._options.headers); } ```
The regex only matches `authorization`, `proxy-authorization`, and `cookie`. Custom headers like `X-API-Key` are not matched.
## Attack Scenario
1. App uses axios with custom auth header: `headers: { 'X-API-Key': 'sk-live-secret123' }` 2. Server returns `302 Location: https://evil.com/steal` 3. follow-redirects sends `X-API-Key: sk-live-secret123` to `evil.com` 4. Attacker captures the API key
## Impact
Any custom auth header set via axios leaks on cross-domain redirect. Extremely common pattern. Affects all axios users in Node.js.
## Suggested Fix
Add a `sensitiveHeaders` option that users can extend, or strip ALL non-standard headers on cross…
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Affected: Ubuntu:Pro:18.04:LTS: node-follow-redirects, Ubuntu:Pro:20.04:LTS: node-follow-redirects, Ubuntu:Pro:22.04:LTS: node-follow-redirects, Ubuntu:Pro:24.04:LTS: node-follow-redirects, Ubuntu:25.10: node-follow-redirects, Ubuntu:Pro:26.04:LTS: node-follow-redirects
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.
Ein Angreifer kann mehrere Schwachstellen in IBM App Connect Enterprise Certified Container ausnutzen, um beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen, Cross-Site-Scripting-Angriffe durchzuführen, Daten zu manipulieren, vertrauliche Informationen offenzulegen oder einen Denial-of-Service-Zustand zu verursachen.