URL parser allowed square brackets in domain names
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.3epss 1.6%
exploitation probability
1.6%top 26% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N
Affected products
Python Software Foundation · CPythonReferences
https://github.com/python/cpython/commit/526617ed68cde460236c973e5d0a8bad4de896bahttps://github.com/python/cpython/commit/90e526ae67b172ed7c6c56e7edad36263b0f9403https://github.com/python/cpython/commit/a7084f6075c9595ba60119ce8c62f1496f50c568https://github.com/python/cpython/commit/b8b4b713c5f8ec0958c7ef8d29d6711889bc94abhttps://github.com/python/cpython/commit/d89a5f6a6e65511a5f6e0618c4c30a7aa5aba56ahttps://github.com/python/cpython/commit/ff4e5c25666f63544071a6b075ae8b25c98b7a32https://github.com/python/cpython/issues/105704https://github.com/python/cpython/pull/129418https://lists.debian.org/debian-lts-announce/2025/03/msg00013.htmlhttps://mail.python.org/archives/list/security-announce@python.org/thread/K4EUG6EKV6JYFIC24BASYOZS4M5XOQIB/https://security.netapp.com/advisory/ntap-20250314-0002/