CVE-2026-91145
Severity CVSS v4.0:
HIGH
Type:
Unavailable / Other
Publication date:
14/09/2026
Last modified:
24/09/2026
Description
Activiti through 7.1.0.M6 fails to validate hash-brace deferred expressions in process variables, allowing attackers to bypass expression filtering. Attackers can inject expressions beginning with #{ that are stored and later evaluated in the full Spring context when a mail task uses variable-backed body fields, enabling method invocation on application beans.
Impact
Base Score 4.0
7.10
Severity 4.0
HIGH
Base Score 3.x
7.10
Severity 3.x
HIGH
References to Advisories, Solutions, and Tools
- https://github.com/Activiti/Activiti
- https://github.com/Activiti/Activiti/blob/7.1.0.M6/activiti-core/activiti-api-impl/activiti-api-process-runtime-impl/src/main/java/org/activiti/runtime/api/impl/ExpressionResolver.java
- https://github.com/Activiti/Activiti/blob/7.1.0.M6/activiti-core/activiti-engine/src/main/java/org/activiti/engine/impl/bpmn/behavior/MailActivityBehavior.java
- https://github.com/Activiti/Activiti/issues/5438
- https://www.vulncheck.com/advisories/activiti-through-7.1.0-m6-expression-injection-via-mail-task
- https://github.com/Activiti/Activiti/issues/5438


