CVE-2026-44431urllib3: Sensitive headers forwarded across origins in proxied low-level redirects

Descripción

urllib3 is an HTTP client library for Python. From 1.23 to before 2.7.0, cross-origin redirects followed from the low-level API via ProxyManager.connection_from_url().urlopen(..., assert_same_host=False) still forward these sensitive headers. This vulnerability is fixed in 2.7.0.

Datos: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Se publican tal como los indican las fuentes, en inglés.

Productos y versiones afectados

Referencias y parches

• https://github.com/urllib3/urllib3/security/advisories/GHSA-qccp-gfcp-xxvc MitigationVendor Advisory
• https://lists.debian.org/debian-lts-announce/2026/06/msg00040.html