Excon does not redact additional sensitive/risky headers when following redirects
Description
Published to the GitHub Advisory Database
Jul 10, 2026
Reviewed
Jul 10, 2026
Published by the National Vulnerability Database
Jul 17, 2026
Last updated
Jul 21, 2026
Impact
The redirect follower middleware previously failed to strip a number of headers that are known to be sensitive and did not provide a way to provide a custom list of headers to strip.
What kind of vulnerability is it? Who is impacted?
This could cause inadvertent leakage of sensitive data for users of the RedirectFollower middleware in cases where the initial request includes header information that is not intended for the new target.
Patches
Patch exists and is released in v1.5.0
Workarounds
Users can backport the fix to a custom redirect follower middleware.
References