diff --git a/app/server/appsmith-plugins/restApiPlugin/src/main/java/com/external/plugins/RestApiPlugin.java b/app/server/appsmith-plugins/restApiPlugin/src/main/java/com/external/plugins/RestApiPlugin.java
index 0f15518af9..6216ee7651 100644
--- a/app/server/appsmith-plugins/restApiPlugin/src/main/java/com/external/plugins/RestApiPlugin.java
+++ b/app/server/appsmith-plugins/restApiPlugin/src/main/java/com/external/plugins/RestApiPlugin.java
@@ -2,14 +2,12 @@ package com.external.plugins;
 
 import com.appsmith.external.models.ActionConfiguration;
 import com.appsmith.external.models.ActionExecutionResult;
-import com.appsmith.external.models.Param;
 import com.appsmith.external.models.Property;
 import com.appsmith.external.models.ResourceConfiguration;
 import com.appsmith.external.plugins.BasePlugin;
 import com.appsmith.external.plugins.PluginExecutor;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import lombok.extern.slf4j.Slf4j;
-import org.json.JSONObject;
 import org.pf4j.Extension;
 import org.pf4j.PluginWrapper;
 import org.springframework.http.HttpHeaders;
@@ -23,7 +21,6 @@ import java.io.IOException;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.stream.Collectors;
 
 public class RestApiPlugin extends BasePlugin {
 
@@ -58,18 +55,11 @@ public class RestApiPlugin extends BasePlugin {
             WebClient.Builder webClientBuilder = WebClient.builder().baseUrl(url);
 
             if (resourceConfiguration.getHeaders() != null) {
-                List<Property> headers = resourceConfiguration.getHeaders();
-                for (Property header : headers) {
-
-                    webClientBuilder.defaultHeader(header.getKey(), header.getValue());
-                }
+                addHeadersToRequest(webClientBuilder, resourceConfiguration.getHeaders());
             }
 
             if (actionConfiguration.getHeaders() != null) {
-                List<Property> headers = actionConfiguration.getHeaders();
-                for (Property header : headers) {
-                    webClientBuilder.defaultHeader(header.getKey(), header.getValue());
-                }
+                addHeadersToRequest(webClientBuilder, actionConfiguration.getHeaders());
             }
 
             return webClientBuilder
@@ -113,5 +103,13 @@ public class RestApiPlugin extends BasePlugin {
         public void resourceDestroy(Object connection) {
 
         }
+
+        private void addHeadersToRequest(WebClient.Builder webClientBuilder, List<Property> headers) {
+            for (Property header : headers) {
+                if (header.getKey() != null && !header.getKey().isEmpty()) {
+                    webClientBuilder.defaultHeader(header.getKey(), header.getValue());
+                }
+            }
+        }
     }
 }
diff --git a/app/server/appsmith-server/src/main/java/com/appsmith/server/exceptions/AppsmithError.java b/app/server/appsmith-server/src/main/java/com/appsmith/server/exceptions/AppsmithError.java
index 3f5d846cb6..fb3585ea7d 100644
--- a/app/server/appsmith-server/src/main/java/com/appsmith/server/exceptions/AppsmithError.java
+++ b/app/server/appsmith-server/src/main/java/com/appsmith/server/exceptions/AppsmithError.java
@@ -15,6 +15,7 @@ public enum AppsmithError {
     PAGE_ID_NOT_GIVEN(400, 4004, "Missing page id. Pleaes input correct page id"),
     PAGE_DOESNT_BELONG_TO_USER_ORGANIZATION(400, 4006, "Page {0} does not belong to the current user {1} organization"),
     UNSUPPORTED_OPERATION(400, 4007, "Unsupported operation"),
+    ACTION_RUN_KEY_VALUE_INVALID(400, 4008, "Invalid template param key value pair: {0}:{1}"),
     UNAUTHORIZED_DOMAIN(401, 4001, "Invalid email domain provided. Please sign in with a valid work email ID"),
     UNAUTHORIZED_ACCESS(401, 4002, "Unauthorized access"),
     INTERNAL_SERVER_ERROR(500, 5000, "Internal server error while processing request"),
diff --git a/app/server/appsmith-server/src/main/java/com/appsmith/server/services/ActionServiceImpl.java b/app/server/appsmith-server/src/main/java/com/appsmith/server/services/ActionServiceImpl.java
index 9014963c12..68a35b69a3 100644
--- a/app/server/appsmith-server/src/main/java/com/appsmith/server/services/ActionServiceImpl.java
+++ b/app/server/appsmith-server/src/main/java/com/appsmith/server/services/ActionServiceImpl.java
@@ -34,6 +34,7 @@ import java.io.StringReader;
 import java.io.StringWriter;
 import java.io.Writer;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.stream.Collectors;
@@ -125,11 +126,19 @@ public class ActionServiceImpl extends BaseService<ActionRepository, Action, Str
     public Mono<ActionExecutionResult> executeAction(ExecuteActionDTO executeActionDTO) {
         String actionId = executeActionDTO.getActionId();
 
-        // 1. Fetch the query from the DB to get the type
+        // 1. Validate input parameters which are required for mustache replacements
+        List<Param> params = executeActionDTO.getParams();
+        for (Param param:params) {
+            if (param.getValue() == null) {
+                return Mono.error(new AppsmithException(AppsmithError.ACTION_RUN_KEY_VALUE_INVALID, param.getKey(), param.getValue()));
+            }
+        }
+
+        // 2. Fetch the query from the DB to get the type
         Mono<Action> actionMono = repository.findById(actionId)
                 .switchIfEmpty(Mono.error(new AppsmithException(AppsmithError.NO_RESOURCE_FOUND, "action", actionId)));
 
-        // 2. Instantiate the implementation class based on the query type
+        // 3. Instantiate the implementation class based on the query type
         Mono<Plugin> pluginMono = actionMono.flatMap(action -> pluginService.findById(action.getPluginId()))
                 .switchIfEmpty(Mono.error(new AppsmithException(AppsmithError.NO_RESOURCE_FOUND, "plugin")));
 
@@ -146,7 +155,7 @@ public class ActionServiceImpl extends BaseService<ActionRepository, Action, Str
         );
 
 
-        // 3. Execute the query
+        // 4. Execute the query
         return actionMono
                 .flatMap(action -> resourceMono.zipWith(pluginExecutorMono, (resource, pluginExecutor) -> {
                     ResourceConfiguration resourceConfiguration;