CVE-2025-0938 Information

Description

The Python standard library functions urllib.parse.urlsplit and urlparse accepted domain names that included square brackets which isn’t valid according to RFC 3986. Square brackets are only meant to be used as delimiters for specifying IPv6 and IPvFuture hosts in URLs. This could result in differential parsing across the Python URL parser and other specification-compliant URL parsers.

Reference

https://github.com/python/cpython/commit/d89a5f6a6e65511a5f6e0618c4c30a7aa5aba56a https://github.com/python/cpython/issues/105704 https://github.com/python/cpython/pull/129418 https://mail.python.org/archives/list/security-announce@python.org/thread/K4EUG6EKV6JYFIC24BASYOZS4M5XOQIB/ The Python standard library functions urllib.parse.urlsplit and urlparse accepted domain names that included square brackets which isn’t valid according to RFC 3986. Square brackets are only meant to be used as delimiters for specifying IPv6 and IPvFuture hosts in URLs. This could result in differential parsing across the Python URL parser and other specification-compliant URL parsers.