The Requests package before 2.20.0 for Python sends an HTTP Authorization header to an http URI upon receiving a same-hostname https-to-http redirect, which makes it easier for remote attackers to discover credentials by sniffing the network.

The resolve_redirects function in sessions.py in requests 2.1.0 through 2.5.3 allows remote attackers to conduct session fixation attacks via a cookie without a host value in a redirect.

Requests (aka python-requests) before 2.3.0 allows remote servers to obtain a netrc password by reading the Authorization header in a redirected request.

Requests (aka python-requests) before 2.3.0 allows remote servers to obtain sensitive information by reading the Proxy-Authorization header in a redirected request.