Vulnerability · Published Oct 20, 2026 · Assigned by curl
CVE-2026-94265Authorization: Negotiate sent to foreign origin
Critical 9.1
In plain English
A critical-severity information exposure in curl from curl. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 56% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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`.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | curl | 8.23.0-r0 | ALPINE-CVE-2026-94265 |
| Alpine:v3.24 | curl | 8.23.0-r0 | ALPINE-CVE-2026-94265 |
| Debian:14 | curl | no fix listed | DEBIAN-CVE-2026-94265 |
Affected products (as reported)
Weakness: CWE-200 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N