urllib's cross-origin redirects preserve credential-bearing request headers, leading to potential credential leakage

Date Aug 25, 2026
Type Vendor advisory
Signal High-risk advisory
Vendor / Product npm ยท urllib
CVE CVE-2026-55553
High-risk advisory CVE-2026-55553

Summary

urllib's cross-origin redirects preserve credential-bearing request headers, leading to potential credential leakage

Why it matters

GitHub has published a reviewed security advisory for urllib. Prioritize it with other application dependency updates.

Operator check

Check whether urllib is present in application dependency manifests, lockfiles, or build images. Review the GitHub advisory and upgrade to a patched version where available.

Sources

PatchBrief uses public sources. It does not scan environments, verify exposure, or replace vendor guidance.