23 Oct 2026 15:48:27 UTC
proxy credentials leak over redirect-to proxy
cve-program · CVE-2026-6253 · Published
CVE-2026-6253
proxy credentials leak over redirect-to proxy
cve-program · severity unknownCVSS unknownCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-6253
Publishedcurl 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. while using the first proxy (using say `http://`), curl is asked to follow a redirect to a URL using another scheme (say `https://`), accessed using a second, different, proxy
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