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index 88e5e21..8543b16 100644
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     <title>JSDoc: Global</title>
 
-    <script src="scripts/prettify/prettify.js"> </script>
+    <script src="https://cdn.jsdelivr.net/gh/google/code-prettify@master/loader/run_prettify.js"> </script>
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index 614ff1e..f041ffd 100644
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+    <script src="https://cdn.jsdelivr.net/gh/google/code-prettify@master/loader/run_prettify.js"> </script>
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index 7bd5096..97cce41 100644
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+    <script src="https://cdn.jsdelivr.net/gh/google/code-prettify@master/loader/run_prettify.js" integrity="sha384-hDHlUtmnjnJimeAhT+DpLqjLdp8vFgSFHhZO1zq2EtqpwFsNM7H5cpSUYqT1Uh2E" crossorigin="anonymous"> </script>
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+    <script src="https://cdn.jsdelivr.net/gh/google/code-prettify@master/loader/run_prettify.js"> </script>
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-250):a&&a()}for(var e=[document.getElementsByTagName("pre"),document.getElementsByTagName("code"),document.getElementsByTagName("xmp")],h=[],k=0;k<e.length;++k)for(var t=0,s=e[k].length;t<s;++t)h.push(e[k][t]);var e=q,l=Date;l.now||(l={now:function(){return+new Date}});var p=0,d,g=/\blang(?:uage)?-([\w.]+)(?!\S)/;m()};window.PR={createSimpleLexer:x,registerLangHandler:k,sourceDecorator:u,PR_ATTRIB_NAME:"atn",PR_ATTRIB_VALUE:"atv",PR_COMMENT:"com",PR_DECLARATION:"dec",PR_KEYWORD:"kwd",PR_LITERAL:"lit",
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diff --git a/docs/stack.js.html b/docs/stack.js.html
index 99afb36..1c0d303 100644
--- a/docs/stack.js.html
+++ b/docs/stack.js.html
@@ -4,7 +4,7 @@
     <meta charset="utf-8">
     <title>JSDoc: Source: stack.js</title>
 
-    <script src="scripts/prettify/prettify.js"> </script>
+    <script src="https://cdn.jsdelivr.net/gh/google/code-prettify@master/loader/run_prettify.js"> </script>
     <script src="scripts/prettify/lang-css.js"> </script>
     <!--[if lt IE 9]>
       <script src="//html5shiv.googlecode.com/svn/trunk/html5.js" integrity="sha384-hDHlUtmnjnJimeAhT+DpLqjLdp8vFgSFHhZO1zq2EtqpwFsNM7H5cpSUYqT1Uh2E" crossorigin="anonymous"></script>
diff --git a/src/config.ts b/src/config.ts
index 7cff619..12b2adf 100644
--- a/src/config.ts
+++ b/src/config.ts
@@ -30,7 +30,7 @@ export const config = {
     // http://mongodb.github.io/node-mongodb-native/3.1/api/MongoClient.html
     options: {
       connectTimeoutMS: 15000,
-      keepAlive: true,
+      // keepAlive: true, // The keepAlive option was deprecated in the Node.js Driver starting from version 5.3. In version 6.0 of the driver, the keepAlive option is permanently set to true
       noDelay: true,
       useNewUrlParser: true,
     },
diff --git a/src/stack.ts b/src/stack.ts
index 0c274e6..9d0b80b 100644
--- a/src/stack.ts
+++ b/src/stack.ts
@@ -2017,6 +2017,9 @@ export class Stack {
 
   private async bindLeftoverAssets(queries: IQuery, locale: string, pointerList: IShelf[]) {
     // const contents = await readFile(getAssetsPath(locale) + '.json')
+    if (!this.sanitizeIQuery(queries)) {
+      throw new Error('Invalid queries provided');
+    }
     const filteredAssets = await this.db.collection(getCollectionName({
       content_type_uid: this.types.assets,
       locale,
@@ -2096,6 +2099,9 @@ export class Stack {
   }
 
   private async getReferencePath(query, locale, currentInclude) {
+    if (!this.sanityQueryAny(query)) {
+      throw new Error('Invalid query provided');
+    }
     const schemas = await this.db.collection(getCollectionName({
         content_type_uid: this.types.content_types,
         locale,
@@ -2184,6 +2190,9 @@ export class Stack {
 
   private async fetchEntries(query: IQuery, locale: string, paths: string[], include: string[], includeAll:
     boolean = false) {
+    if (!this.sanitizeIQuery(query)) {
+      throw new Error('Invalid queries provided');
+    }
     const result = await this.db.collection(getCollectionName({
         content_type_uid: 'entries',
         locale,
@@ -2376,5 +2385,30 @@ export class Stack {
       paths,
     }
   }
-  // tslint:disable-next-line: max-file-line-count
+
+  private sanitizeIQuery(query: IQuery): boolean {
+    if (!query || typeof query !== 'object' || Array.isArray(query)) {
+      return false;
+    }
+    if (!query || !Array.isArray(query.$or)) {
+      return false;
+    }
+    for (const item of query.$or) {
+      if (
+        typeof item._content_type_uid !== 'string' ||
+        typeof item.uid !== 'string' ||
+        (item._version && typeof item._version.$exists !== 'boolean') ||
+        (item.locale && typeof item.locale !== 'string')
+      ) {
+        return false;
+      }
+    }
+    return true;
+  }
+  private sanityQueryAny(query: any): boolean {
+    if (!query || typeof query !== 'object' || Array.isArray(query)) {
+      return false;
+    }
+    return true;
+  }
 }
diff --git a/test/expressions.ts b/test/expressions.ts
index 5fb5193..9e4e02f 100644
--- a/test/expressions.ts
+++ b/test/expressions.ts
@@ -90,7 +90,7 @@ describe('# Expressional Operators', () => {
     test('.regex()', () => {
       return Stack.contentType('blog')
         .entries()
-        .regex('title', '/^Blog Two$/', 'g')
+        .regex('title', '/^Blog Two$/', 'i')
         .find()
         .then((result: any) => {
           checkEntries(result)
diff --git a/typings/config.d.ts b/typings/config.d.ts
index 7150361..29600fa 100644
--- a/typings/config.d.ts
+++ b/typings/config.d.ts
@@ -28,7 +28,6 @@ export declare const config: {
         locale: string;
         options: {
             connectTimeoutMS: number;
-            keepAlive: boolean;
             noDelay: boolean;
             useNewUrlParser: boolean;
         };
diff --git a/typings/stack.d.ts b/typings/stack.d.ts
index 686c76e..534a533 100644
--- a/typings/stack.d.ts
+++ b/typings/stack.d.ts
@@ -1092,4 +1092,6 @@ export declare class Stack {
     private bindReferences;
     private includeAllReferencesIteration;
     private getAllReferencePaths;
+    private sanitizeIQuery;
+    private sanityQueryAny;
 }