A security regression of CVE-2019-9636 was discovered in python since commit d537ab0ff9767ef024f26246899728f0116b1ec3 affecting versions 2.7, 3.5, 3.6, 3.7 and from v3.8.0a4 through v3.8.0b1, which still allows an attacker to exploit CVE-2019-9636 by abusing the user and password parts of a URL. When an application parses user-supplied URLs to store cookies, authentication credentials, or other kind of information, it is possible for an attacker to provide specially crafted URLs to make the application locate host-related information (e.g. cookies, authentication data) and send them to a different host than where it should, unlike if the URLs had been correctly parsed. The result of an attack may vary based on the application.
https://usn.ubuntu.com/4127-2/
https://usn.ubuntu.com/4127-1/
https://security.netapp.com/advisory/ntap-20190617-0003/
https://python-security.readthedocs.io/vuln/urlsplit-nfkc-normalization2.html
https://lists.debian.org/debian-lts-announce/2020/08/msg00034.html
https://lists.debian.org/debian-lts-announce/2020/07/msg00011.html
https://lists.debian.org/debian-lts-announce/2019/06/msg00022.html
https://github.com/python/cpython/commit/fd1771dbdd28709716bd531580c40ae5ed814468
https://github.com/python/cpython/commit/f61599b050c621386a3fc6bc480359e2d3bb93de
https://github.com/python/cpython/commit/8d0ef0b5edeae52960c7ed05ae8a12388324f87e
https://github.com/python/cpython/commit/250b62acc59921d399f0db47db3b462cd6037e09
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-10160
https://access.redhat.com/errata/RHSA-2019:2437
https://access.redhat.com/errata/RHSA-2019:1700
https://access.redhat.com/errata/RHSA-2019:1587
http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html
http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00042.html