Silverstripe Advanced Workflow is a highly configurable step-based workflow module. Prior to 6.4.5, 7.1.3, and 7.2.1, an attacker with permission to author the advanced workflow email template can place a specially crafted server-side template payload in NotifyUsersWorkflowAction.EmailTemplate. When NotifyUsersWorkflowAction renders the field through the Silverstripe template engine SSTemplateParser, the payload can cause PHP evaluation and arbitrary code execution on the server; the regression coverage is in tests/php/WorkflowEngineTest.php. This issue is fixed in versions 6.4.5, 7.1.3, and 7.2.1.

A server-side template injection vulnerability exists in Silverstripe Advanced Workflow module prior to versions 6.4.5, 7.1.3, and 7.2.1. An attacker with permission to author advanced workflow email templates can inject a malicious payload into the NotifyUsersWorkflowAction.EmailTemplate field. When rendered by the SSTemplateParser template engine, the payload can trigger PHP evaluation and arbitrary code execution on the server. The vulnerability requires the attacker to have template authoring permissions, limiting the attack surface but not eliminating risk in multi-user environments. Fixes have been released in versions 6.4.5, 7.1.3, and 7.2.1. Regression test coverage has been added in tests/php/WorkflowEngineTest.php. Users are strongly advised to upgrade to the patched versions immediately.