OpenMRS has Stored Velocity SSTI to RCE via ConceptReferenceRange

### 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/