diff --git a/main/plugins/org.talend.librariesmanager/resources/java/routines/TalendString.java b/main/plugins/org.talend.librariesmanager/resources/java/routines/TalendString.java
index d3ebc6a251..d6b35c15d5 100644
--- a/main/plugins/org.talend.librariesmanager/resources/java/routines/TalendString.java
+++ b/main/plugins/org.talend.librariesmanager/resources/java/routines/TalendString.java
@@ -5,7 +5,7 @@
 // ============================================================================
 package routines;
 
-import java.util.Random;
+import java.security.SecureRandom;
 import java.util.Vector;
 
 public class TalendString {
@@ -74,20 +74,20 @@ public class TalendString {
      * {example} getAsciiRandomString(6) # Art34Z
      */
     public static String getAsciiRandomString(int length) {
-        Random random = new Random();
+        SecureRandom random = new SecureRandom();
         int cnt = 0;
-        StringBuffer buffer = new StringBuffer();
+        StringBuilder builder = new StringBuilder();
         char ch;
         int end = 'z' + 1;
         int start = ' ';
         while (cnt < length) {
             ch = (char) (random.nextInt(end - start) + start);
             if (Character.isLetterOrDigit(ch)) {
-                buffer.append(ch);
+                builder.append(ch);
                 cnt++;
             }
         }
-        return buffer.toString();
+        return builder.toString();
     }
 
     /**
diff --git a/main/plugins/org.talend.utils/src/main/java/org/talend/utils/IdGenerator.java b/main/plugins/org.talend.utils/src/main/java/org/talend/utils/IdGenerator.java
index 9c023d5caf..c5dc08143a 100644
--- a/main/plugins/org.talend.utils/src/main/java/org/talend/utils/IdGenerator.java
+++ b/main/plugins/org.talend.utils/src/main/java/org/talend/utils/IdGenerator.java
@@ -12,7 +12,7 @@
 // ============================================================================
 package org.talend.utils;
 
-import java.util.Random;
+import java.security.SecureRandom;
 
 /**
  * DOC amaumont class global comment. Detailled comment <br/>
@@ -30,20 +30,20 @@ public class IdGenerator {
      * {example} getAsciiRandomString(6) # Art34Z
      */
     public static String getAsciiRandomString(int length) {
-        Random random = new Random();
+        SecureRandom random = new SecureRandom();
         int cnt = 0;
-        StringBuffer buffer = new StringBuffer();
+        StringBuilder builder = new StringBuilder();
         char ch;
         int end = 'z' + 1;
         int start = ' ';
         while (cnt < length) {
             ch = (char) (random.nextInt(end - start) + start);
             if (Character.isLetterOrDigit(ch)) {
-                buffer.append(ch);
+                builder.append(ch);
                 cnt++;
             }
         }
-        return buffer.toString();
+        return builder.toString();
     }
 
 }