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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
Low
Partial data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products
activiti:activiti
References 5
https://github.com/Activiti/Activiti
disclosure@vulncheck.com
https://github.com/Activiti/Activiti/blob/7.1.0.M6/activiti-core/activiti-api-i…
disclosure@vulncheck.com
https://github.com/Activiti/Activiti/blob/7.1.0.M6/activiti-core/activiti-engin…
disclosure@vulncheck.com
https://github.com/Activiti/Activiti/issues/5438
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/activiti-through-7.1.0-m6-expression-injec…
disclosure@vulncheck.com