CVE-2026-28695: Craft affected by authenticated RCE via Twig SSTI - create() function + Symfony Process gadget

Severity: high (CVSS 7.2 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-03-04 · updated 2026-06-17
Weakness: CWE-1336

Description

Craft is a content management system (CMS). There is an authenticated admin RCE in Craft CMS 5.8.21 via Server-Side Template Injection using the create() Twig function combined with a Symfony Process gadget chain. The create() Twig function exposes Craft::createObject(), which allows instantiation of arbitrary PHP classes with constructor arguments. Combined with the bundled symfony/process dependency, this enables RCE. This bypasses the fix implemented for CVE-2025-57811 (patched in 5.8.7). This vulnerability is fixed in 5.9.0-beta.1 and 4.17.0-beta.1.

Affected products

craftcms cms: from 4.0.0 (excl.) before 4.17.0; from 5.0.0 (excl.) before 5.9.0; 4.0.0, 4.0.0-rc1, 4.0.0-rc2, 4.0.0-rc3, 5.0.0, 5.0.0-rc1 — fixed in 4.17.0, 5.9.0

How to fix

Upgrade to a fixed version: craftcms cms 4.17.0, 5.9.0. Check the vendor advisory for mitigations.

References

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