diff --git a/inside/User.php b/inside/User.php
index 65c3e30..5bc3b7a 100644
--- a/inside/User.php
+++ b/inside/User.php
@@ -56,6 +56,7 @@ class User {
                 $this->id = -1;
                 return false;
             } else {
+                /* Validate user supplied data. */
                 if (strlen(stripcslashes($data['username'])) < 3 || strlen(stripcslashes($data['username'])) > 12 ) {
                     notify("Brukernavnet må være mellom 3 og 12 tegn.");
                     $this->id = -1;
@@ -72,6 +73,12 @@ class User {
                     $this->id = -1;
                     return false;
                 }
+                /* No double nor single quotes */
+                if(preg_match('/["\'\\]+/', $data['password1'])) {
+                    notify("Passordet kan ikke inneholde enkel- eller dobbelfnutt eller bakslask.");
+                    $this->id = -1;
+                    return false;
+                }
                 if ($data['password1'] != $data['password2']) {
                     notify("Passordene var ikke like.");
                     $this->id = -1;
diff --git a/inside/migration/js/byebye_inside.js b/inside/migration/js/byebye_inside.js
index 1e37295..2bba94d 100644
--- a/inside/migration/js/byebye_inside.js
+++ b/inside/migration/js/byebye_inside.js
@@ -10,10 +10,14 @@ function init_validation() {
             password: {
                 required: true,
                 minlength: 8,
+                noquotes: true,
+                nobackslashes: true,
             },
             password_check: {
                 required: true,
                 minlength: 8,
+                noquotes: true,
+                nobackslashes: true,
                 equalTo: "#id_password",
             },
         },
diff --git a/inside/migration/js/custom_validators.js b/inside/migration/js/custom_validators.js
index 2542aa1..3bf1361 100644
--- a/inside/migration/js/custom_validators.js
+++ b/inside/migration/js/custom_validators.js
@@ -1,3 +1,9 @@
 jQuery.validator.addMethod("lettersonly", function(value, element) {
 	return this.optional(element) || /^[a-z]+$/.test(value);
 }, "Please enter only letters (english alphabet)."); 
+jQuery.validator.addMethod("noquotes", function(value, element) {
+	return this.optional(element) || ! /['"]+/.test(value);
+}, "No single or double quotes, please."); 
+jQuery.validator.addMethod("noescape", function(value, element) {
+	return this.optional(element) || ! /[\\]+/.test(value);
+}, "No backslashes, please.");