#VU18355 Input validation error in Python - CVE-2019-9636

Vulnerability identifier: #VU18355

Vulnerability risk: Medium

CVSSv4.0: 4.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-9636

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 gain access to sensitive information.

The vulnerability exists due to insufficient validation of user-supplied input when processing data in Unicode encoding with an incorrect netloc during NFKC normalization. A remote attacker can gain access to sensitive information.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Python: 2.7 - 2.7.2150, 3.0 - 3.0.1, 3.1 - 3.1.2150, 3.2 - 3.2.2150, 3.3.0 - 3.3.7, 3.4.0 - 3.4.10, 3.5.0 - 3.5.7, 3.6 - 3.6.8, 3.7 - 3.7.2

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External links
https://bugs.python.org/issue36216
https://github.com/python/cpython/pull/12201

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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.