CVE-2026-6253 proxy credentials leak over redirect-to proxy

curl might erroneously pass on credentials for a first proxy to a second proxy. This can happen when the following conditions are true: 1. curl is setup to use specific different proxies for different URL schemes 2. the first proxy needs credentials 3. the second proxy uses no credentials 4. whil...

CVE-2026-6253

The curl (and libcurl ) library is vulnerable to a credential leak where it might erroneously pass proxy credentials from a first proxy to a second proxy. This occurs when different proxies are configured for different URL schemes; if a request initiated via a credentialed first proxy is redirect...