CVE-2026-11407: Pimcore CMS 12.3.8 Twig Sandbox Bypass – RCE & Data Exposure Risk

Technical summary

The vulnerability stems from empty implementations of checkMethodAllowed() and checkPropertyAllowed() methods in Pimcore's custom Twig SecurityPolicy. These methods are meant to restrict what PHP methods and properties can be accessed from Twig templates, but the lack of validation logic allows authenticated attackers to call arbitrary methods on objects. The pimcore_* function wildcard in Twig further circumvents intended restrictions, exposing all Pimcore Twig functions to abuse. An attacker can construct Twig templates containing PHP object gadget chains to achieve code execution or access sensitive data. Attack surface is the DataObject ClassDefinition Layout\Text component, which processes user-supplied template content.

Business impact

Organizations running Pimcore 12.3.8 face risk of data exfiltration (file reads, database queries), unauthorized system modifications, and potential remote code execution if an administrator account is compromised or if a trusted admin is malicious. This is particularly serious in multi-tenant or SaaS environments where content editors or partners have admin access. Breach of server-side resources and customer data are realistic outcomes. Regulatory and compliance implications depend on data exposure scope and industry.

Affected systems

Pimcore CMS/DXP version 12.3.8 is confirmed vulnerable. Earlier and later versions have not been detailed in available advisories; verify against Pimcore's official security statement for full version scope and mitigation timeline.

Exploitability

Exploitation requires valid administrative credentials and the ability to submit Twig templates via the DataObject ClassDefinition component. No user interaction is needed once the template is injected. Network access is required but not authentication bypass. The attack is reliably weaponizable for attackers with admin or high-privilege access, making this a high-confidence exploitation scenario in compromised-account or insider-threat contexts.

Remediation

Upgrade Pimcore CMS/DXP to a patched version (verify against Pimcore's official advisory for the specific version numbers and release dates). If immediate patching is not feasible, restrict admin account access to trusted personnel, disable or heavily monitor the DataObject ClassDefinition Layout\Text component, and enforce code review for any Twig templates before deployment. Consider network segmentation to limit lateral movement if a template injection occurs.

Patch guidance

Check Pimcore's official security advisories and release notes for a patched version of 12.3.8 or a migration path. Apply the patch in a staging environment first and verify that Twig template security policies are properly enforced post-patch. Test admin workflows to ensure the patch does not break legitimate template functionality.

Detection guidance

Monitor for suspicious Twig templates submitted to DataObject ClassDefinition components, especially those containing method calls on non-whitelisted PHP objects or accessing dangerous functions (file I/O, database queries, system execution). Log and alert on admin account activity involving template creation or modification, and examine template content for gadget chain patterns or calls to restricted Pimcore functions. Look for unusual database queries or file access initiated from Twig template processing.

Why prioritize this

This is a HIGH-severity issue (CVSS 7.2) affecting a content management platform. While it requires admin credentials, the combination of sandbox bypass, code execution potential, and data access makes it critical for any organization using Pimcore 12.3.8 in a sensitive context. Prioritize patching if the instance handles customer data, financial records, or sensitive business content.

Risk score, explained

CVSS 3.1 score of 7.2 reflects high impact (confidentiality, integrity, availability all affected) with high attack complexity (admin authentication required) and network accessibility. The score does not decrease for authentication burden because a single compromised admin account or insider threat poses severe risk. The presence of gadget chain exploitation potential justifies the upper end of the HIGH range.

Frequently asked questions