#VU103812 Input validation error in Python - CVE-2025-0938

Vulnerability identifier: #VU103812

Vulnerability risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-0938

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Python
Universal components / Libraries / Scripting languages

Vendor: Python.org

Description

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to urllib.parse.urlsplit and urlparse accept domain names with square brackets. A remote attacker can pass specially crafted input to the application and bypass implemented security restrictions.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Python: All versions

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External links
https://github.com/python/cpython/commit/90e526ae67b172ed7c6c56e7edad36263b0f9403
https://github.com/python/cpython/commit/a7084f6075c9595ba60119ce8c62f1496f50c568
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/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.