An administrator with workflow definition entitlements can use DTD to perform malicious operations, including but not limited to file read, file write, and code execution.
An administrator with report and template entitlements in Apache Syncope 1.2.x before 1.2.11 and 2.0.x before 2.0.8 can use XSL Transformations (XSLT) to perform malicious operations, including but not limited to file read, file write, and code execution.