#VU66467 Path traversal in Babel - CVE-2021-42771

Vulnerability identifier: #VU66467

Vulnerability risk: Medium

CVSSv4.0: 1.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-42771

CWE-ID: CWE-22

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Babel
Web applications / Modules and components for CMS

Vendor: The Babel Team

Description

The vulnerability allows a remote attacker to user compromise the affected system.

The vulnerability exists due to input validation error when processing directory traversal sequences within the locale .dat files in Babel.Locale. A remote user can load a malicious .dat file containing serialized Python objects and execute arbitrary code on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Babel: 2.0 - 2.9.0

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External links
https://www.tenable.com/security/research/tra-2021-14
https://lists.debian.org/debian-lts/2021/10/msg00040.html
https://github.com/python-babel/babel/pull/782
https://lists.debian.org/debian-lts-announce/2021/10/msg00018.html
https://www.debian.org/security/2021/dsa-5018

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

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