Description
When processing an HTTP redirect to a URL containing userinfo (a `username:password` component), curl might erroneously retain and re-transmit the original host's HTTP Negotiate authentication state. Consequently, a malicious server can trigger a redirect containing arbitrary userinfo to force curl to send a freshly minted Kerberos ticket—generated using the ambient identity of the client process to an untrusted third-party host, effectively bypassing the domain-scoping restrictions normally enforced by the absence of `--location-trusted`.
References4
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 1% percentile: 56 · as of 9 November 2026
- CWE
- CWE-200
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