ICM: Protect RCE sandbox (#4128)

Protect sandbox environment against remote code execution.

Author: w-javed

src/promptflow-core/CHANGELOG.md

@@ -1,5 +1,11 @@
 # promptflow-core package
 
+## v1.18.2 (2026.4.21)
+
+### Bugs fixed
+
+- Resolving an RCE using PF_USE_SANDBOX_FOR_JINJA.
+
 ## v1.18.1 (2025.6.10)
 
 ### Bugs fixed

src/promptflow-core/promptflow/executor/_service/utils/service_utils.py

@@ -71,7 +71,7 @@ def generate_error_response(ex: Union[dict, Exception]):
 def set_environment_variables(environment_variables: Mapping[str, Any]):
     def filter_env_variables(environ: Dict[str, Any]) -> Dict[str, Any]:
         """Remove problematic environment variables."""
-        deny_list = {"PYTHONWARNINGS", "BROWSER"}
+        deny_list = {"PYTHONWARNINGS", "BROWSER", "PF_USE_SANDBOX_FOR_JINJA"}
         return {k: v for k, v in environment_variables.items() if k not in deny_list}
 
     if isinstance(environment_variables, dict) and environment_variables: