A Server-Side Template Injection (SSTI) vulnerability exists in Mautic's theme engine.
Priority MEDIUM 44CWE-1336Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-1336.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00571 47th percentileScored 2026-11-07
Fix Fixed mautic/core: 4.4.20, 5.2.11, 6.0.9 +1mautic/core (Packagist): 5.2.11, 6.0.9, 7.1.2
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | mautic/core | 1.3.0 to before 4.4.20; 5.0.0 to before 5.2.11; 6.0.0 to before 6.0.9; 7.0.0 to before 7.1.2 | 4.4.20, 5.2.11, 6.0.9, 7.1.2 | Patch available | CNA |
| — | mautic/core (Packagist) | 1.3.0 and later | — | No fix listed | GHSA-9fx4-7cmj-47vg |
| — | mautic/core (Packagist) | 5.0.0 to before 5.2.11 | 5.2.11 | Patch available | GHSA-9fx4-7cmj-47vg |
| — | mautic/core (Packagist) | 6.0.0 to before 6.0.9 | 6.0.9 | Patch available | GHSA-9fx4-7cmj-47vg |
| — | mautic/core (Packagist) | 7.0.0 to before 7.1.2 | 7.1.2 | Patch available | GHSA-9fx4-7cmj-47vg |
- mautic/core Vendor— Affected 1.3.0 to before 4.4.20; 5.0.0 to before 5.2.11; 6.0.0 to before 6.0.9; 7.0.0 to before 7.1.2 Fixed in 4.4.20, 5.2.11, 6.0.9, 7.1.2 Patch available CNA
- mautic/core (Packagist) Vendor— Affected 1.3.0 and later Fixed in — No fix listed GHSA-9fx4-7cmj-47vg
- mautic/core (Packagist) Vendor— Affected 5.0.0 to before 5.2.11 Fixed in 5.2.11 Patch available GHSA-9fx4-7cmj-47vg
- mautic/core (Packagist) Vendor— Affected 6.0.0 to before 6.0.9 Fixed in 6.0.9 Patch available GHSA-9fx4-7cmj-47vg
- mautic/core (Packagist) Vendor— Affected 7.0.0 to before 7.1.2 Fixed in 7.1.2 Patch available GHSA-9fx4-7cmj-47vg
Remediation
- Fix · CNA mautic/core Fixed in 4.4.20, 5.2.11, 6.0.9, 7.1.2
- Fix · GHSA-9fx4-7cmj-47vg mautic/core (Packagist) Fixed in 5.2.11 Advisory →
- Fix · GHSA-9fx4-7cmj-47vg mautic/core (Packagist) Fixed in 6.0.9 Advisory →
- Fix · GHSA-9fx4-7cmj-47vg mautic/core (Packagist) Fixed in 7.1.2 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-9558
- 2026-10-03 Alias added: GHSA-9fx4-7cmj-47vg
- 2026-10-25 EPSS moved to the below the 50th percentile
References
Sources
- CVE-2026-9558 · CVE Program
- CVE-2026-9558 · NVD
- FIRST EPSS
- GHSA-9fx4-7cmj-47vg · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences