This page tracks the Ubuntu fix status. The vulnerability itself is described on the main CVE page. View CVE-2026-91766 →

UBUNTU-CVE-2026-91766

When the http:// stream wrapper follows a redirect it forwards the user-supplied Authorization, Cookie and Proxy-Authorization headers unchanged, even...

Original description

The description as published by the source.

When the http:// stream wrapper follows a redirect it forwards the user-supplied Authorization, Cookie and Proxy-Authorization headers unchanged, even when the redirect target is a different host, a different port, or a downgrade from HTTPS to HTTP. A server that can steer a redirect therefore receives credentials that were only meant for the original origin. This is the same class of issue that libcurl fixed in 7.58.0 ( CVE-2018-1000007 https://github.com/advisories/GHSA-g7x2-hrfp-pv5f ).

Source: OSV.dev (Open Source Vulnerabilities) OSV