Path traversal in mjml framework

1) Path traversal

EUVDB-ID: #VU29232

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

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

CPE2.3

• cpe:2.3:a:mjml.io:mjml:1.0.0:*:*:*:*:*:*:*
• cpe:2.3:a:mjml.io:mjml:1.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:mjml.io:mjml:1.0.3:*:*:*:*:*:*:*

External links

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