Critical severity9.9NVD Advisory· Published May 29, 2026· Updated May 29, 2026

CVE-2026-9558

Description

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.

AI Insight

LLM-synthesized narrative grounded in this CVE's description and references.

Affected products

Mautic/Mauticinferred2 versions
(expand)+ 1 more
- (no CPE)
- (no CPE)

Patches

Vulnerability mechanics

References

github.com/mautic/mautic/security/advisories/GHSA-9fx4-7cmj-47vgnvd

News mentions

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