Path traversal in mjml framework

1) Path traversal

EUVDB-ID: #VU29232

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-12827

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform directory traversal attacks.

The vulnerability exists due to input validation error when processing the "mj-include" directive within an MJML. A remote attacker can send a specially crafted HTTP request and read arbitrary files on the system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

mjml: 1.0.0 - 4.6.2

External links

http://packetstormsecurity.com/files/158111/MJML-4.6.2-Path-Traversal.html
http://seclists.org/fulldisclosure/2020/Jun/23
http://github.com/mjmlio/mjml/commit/30e29ed2cdaec8684d60a6d12ea07b611c765a12
http://github.com/mjmlio/mjml/releases/tag/v4.6.3
http://mjml.io/community
http://rcesecurity.com
http://twitter.com/mjmlio

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.