Description
MJML through 4.18.0 allows mj-include directory traversal to test file existence and (in the type="css" case) read files. NOTE: this issue exists because of an incomplete fix for CVE-2020-12827.
References1
Metrics
- CVSS 3.1
-
4.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:L - EPSS — exploit probability
- 0% percentile: 18 · as of 11 November 2026
- CWE
- CWE-36
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.