Improper URL validation in Python urllib.parse

1) Input validation error

EUVDB-ID: #VU72618

Risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2023-24329

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass implemented filters.

The vulnerability exists due to insufficient validation of URLs that start with blank characters within urllib.parse component of Python. A remote attacker can pass specially crafted URL to bypass existing filters.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Python: 3.7 - 3.11.3

CPE2.3

• cpe:2.3:a:python_org:python:3.7:*:*:*:*:*:*:*
• cpe:2.3:a:python_org:python:*:*:*:*:*:*:*:*
• cpe:2.3:a:python_org:python:3.7.1:*:*:*:*:*:*:*
• cpe:2.3:a:python_org:python:3.7.2:*:*:*:*:*:*:*
• cpe:2.3:a:python_org:python:3.7.3:*:*:*:*:*:*:*
• cpe:2.3:a:python_org:python:3.7.4:*:*:*:*:*:*:*
• cpe:2.3:a:python_org:python:3.7.5:*:*:*:*:*:*:*
• cpe:2.3:a:python_org:python:3.7.6:*:*:*:*:*:*:*
• cpe:2.3:a:python_org:python:3.7.7:*:*:*:*:*:*:*
• cpe:2.3:a:python_org:python:3.7.8:*:*:*:*:*:*:*

External links

https://pointernull.com/security/python-url-parse-problem.html
https://github.com/python/cpython/pull/99421
https://github.com/python/cpython/issues/102153
https://docs.python.org/3.10/whatsnew/changelog.html#python-3-10-12-final
https://docs.python.org/3.9/whatsnew/changelog.html#python-3-9-17-final
https://docs.python.org/3.8/whatsnew/changelog.html#python-3-8-17-final
https://docs.python.org/3.7/whatsnew/changelog.html#python-3-7-17-final
https://docs.python.org/3.11/whatsnew/changelog.html#python-3-11-14-final

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.