diff --git a/src/package_io/sanity_check.star b/src/package_io/sanity_check.star
index 058b216c6..170b84e4c 100644
--- a/src/package_io/sanity_check.star
+++ b/src/package_io/sanity_check.star
@@ -138,6 +138,46 @@ PARTICIPANT_MATRIX_PARAMS = {
     },
 }
 
+PORT_PUBLISHER_PARAMS = {
+    "port_publisher": {
+        "el": [
+            "enabled",
+            "public_port_start",
+            "nat_exit_ip",
+        ],
+        "cl": [
+            "enabled",
+            "public_port_start",
+            "nat_exit_ip",
+        ],
+        "vc": [
+            "enabled",
+            "public_port_start",
+            "nat_exit_ip",
+        ],
+        "remote_signer": [
+            "enabled",
+            "public_port_start",
+            "nat_exit_ip",
+        ],
+        "additional_services": [
+            "enabled",
+            "public_port_start",
+            "nat_exit_ip",
+        ],
+        "mev": [
+            "enabled",
+            "public_port_start",
+            "nat_exit_ip",
+        ],
+        "other": [
+            "enabled",
+            "public_port_start",
+            "nat_exit_ip",
+        ],
+    },
+}
+
 SUBCATEGORY_PARAMS = {
     "network_params": [
         "network",
@@ -289,16 +329,6 @@ SUBCATEGORY_PARAMS = {
     "ethereum_genesis_generator_params": [
         "image",
     ],
-    "port_publisher": [
-        "nat_exit_ip",
-        "el",
-        "cl",
-        "vc",
-        "remote_signer",
-        "additional_services",
-        "mev",
-        "other",
-    ],
 }
 
 ADDITIONAL_SERVICES_PARAMS = [
@@ -366,12 +396,41 @@ def validate_params(plan, input_args, category, allowed_params):
                 )
 
 
+def validate_nested_params(
+    plan, input_args, category, nested_param_definition, special_keys=None
+):
+    if category not in input_args:
+        return
+
+    special_keys = special_keys or []
+    allowed_top_level_keys = list(nested_param_definition.keys()) + special_keys
+
+    # Validate top-level keys
+    for param in input_args[category].keys():
+        if param not in allowed_top_level_keys:
+            fail(
+                "Invalid parameter {0} for {1}, allowed fields: {2}".format(
+                    param, category, allowed_top_level_keys
+                )
+            )
+
+    # Validate nested parameters
+    for sub_param in input_args[category]:
+        if sub_param not in special_keys and sub_param in nested_param_definition:
+            validate_params(
+                plan,
+                input_args[category],
+                sub_param,
+                nested_param_definition[sub_param],
+            )
+
+
 def sanity_check(plan, input_args):
     # Checks participants
     deep_validate_params(
         plan, input_args, "participants", PARTICIPANT_CATEGORIES["participants"]
     )
-    # Checks participants_matrix
+    # Checks participants_matrix (uses original logic for arrays of objects)
     if "participants_matrix" in input_args:
         for sub_matrix_participant in input_args["participants_matrix"]:
             if (
@@ -394,6 +453,15 @@ def sanity_check(plan, input_args):
                     ],
                 )
 
+    # Checks port_publisher (uses new generic validation for key-value mappings)
+    validate_nested_params(
+        plan,
+        input_args,
+        "port_publisher",
+        PORT_PUBLISHER_PARAMS["port_publisher"],
+        ["nat_exit_ip"],
+    )
+
     # Checks additional services
     if "additional_services" in input_args:
         for additional_services in input_args["additional_services"]:
@@ -414,6 +482,7 @@ def sanity_check(plan, input_args):
         combined_root_params = (
             PARTICIPANT_CATEGORIES.keys()
             + PARTICIPANT_MATRIX_PARAMS.keys()
+            + PORT_PUBLISHER_PARAMS.keys()
             + SUBCATEGORY_PARAMS.keys()
             + ADDITIONAL_CATEGORY_PARAMS.keys()
         )