CVE-2026-9558

critical · 9.9

A Server-Side Template Injection (SSTI) vulnerability exists in Mautic's theme engine. The platform renders uploaded Twig templates without a sandbox or strict function restrictions. Authenticated users with permissions to create or upload themes can abuse this to execute arbitrary code on the hosting server (Remote Code Execution) or access restricted system files and configuration settings.

9.9

CVSS

0.6%

EPSS (exploit prob.)

46th

EPSS percentile

2026-05-29

Published

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Weaknesses

CWE-1336

References

https://github.com/mautic/mautic/security/advisories/GHSA-9fx4-7cmj-47vg

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-9558