Impact The "ConceptReferenceRangeUtility.evaluateCriteria()" method in OpenMRS Core evaluates database-stored criteria strings as Apache Velocity templates without any sandbox configuration. The "VelocityEngine" is initialized with only logging properties and no"SecureUberspector", leaving the default "UberspectImpl" in place, which allows unrestricted Java reflection through template expressions. A user with the "Manage Concepts" privilege can store a malicious Velocity template expression in a concept's reference range criteria field. This payload is then executed automatically whenever a user or API call validates an observation against the affected concept. The Velocity context exposes "$patient" (the "Person" / "Patient" object), "$obs" (the "Obs" object), and "$fn" (the "ConceptReferenceRangeUtility" instance with access to the full OpenMRS service layer). Persistent Remote Code Execution: The payload persists in the concept_reference_range database table (VARCHAR 65535). A single compromised concept for a common clinical measurement executes the payload on every subsequent observation validation across all users, API clients, and integrations in the facility. Privilege Escalation: The Manage Concepts privilege is a content-management function, defined as "Able to add/edit/delete concept entries", not an administrative privilege. Multiple non-admin staff per facility typically hold this privilege. The attacker escalates from concept dictionary management to arbitrary code execution as the Tomcat application server process. PHI Exfiltration: The Velocity context objects directly expose patient data without requiring OS-level RCE. Patches This is fixed in 2.8.6 and 2.7.9 as well as future versions. Workarounds Ensure the "Manage Concepts" privilege is restricted to only authorized users and carefully audit any "ConceptReferenceRanges" in the database. Resources https://github.com/openmrs/openmrs-core/commit/8d1c193 https://www.machinespirits.com/advisory/1e8430/