Unable to launch ProxySG management console with JAVA JRE error.

Products

• ProxySG Software - SGOS

Issue/Introduction

Customer may encounter issue of accessing legacy management console (E.g. SGOS 6.6.3.2) after JAVA JRE version upgraded 1.8.0_131 or higher.

"Application Error"
Application Blocked. Click for details
Your security settings have blocked an application from running with an out-of-date or expired version of Java.
The following resource is signed with a weak signature algorithm MD5withRSA and is treated as unsigned: https://<proxy-ip>:8082/Secure/Local/console/r183872/applets.jar

 

Environment

Windows Operating Environment
ProxySG Management Console

Cause

The issue in connection with new JAVA security checkup for weak algorithm or key was used to sign a JAR file and those JAR file signed with DSA keys less than 1024 bits will be treated as unsigned JARs.

Resolution

Workaround:
This issue doesn't impact to new SGOS and customer can disable this minimum key length requirement check by editing the java.security file as workaround solution for accessing to legacy ProxySG management console. 
Example:
 1. locate the java.security file: C:\Program Files (x86)\Java\jre1.8.0_144\lib\security\java.security
 2. Open with text editor. Eg: Notepad.exe
 3. Find the key words  "jdk.jar.disabledAlgorithms=MD2, MD5, RSA keySize < 1024"
4. Disable this algorithm by adding  # character in front.
    #jdk.jar.disabledAlgorithms=MD2, MD5, RSA keySize < 1024
 5. Save and test again accessing the management console.