Cisco ASA 5505: Error Code: ssl_error_no_cypher_overlap

Posted: 10th December 2012 by admin in Uncategorized

For those who have an ASA 5505 firewall with no VPN-3DES-AES license, it can be frustrating to get ASDM to work… it definitely was for me.

When trying to access ASDM via HTTPS you’ll get the error code “((Error code: ssl_error_no_cypher_overlap)”. This means the firewall is using a type of encryption your browser cannot will not comprehend, yet.

Run this command: ssl encryption des-sha1 null-sha1

If you try to access ASDM after doing this, you will most likely still get the same error. For the next step you will need Firefox, as I have not tried this on IE, Chrome, or Safari.

In the URL bar of Firefox, type “about:config”. This will take you to the Firefox config page, and don’t worry about the void your warranty message… it’s a free product, remember?

Scroll down to the “security.ssl3.rsa_des_sha” and the “security.ssl3.rsa_null_sha” option and double click to set it to true.

Close the about:config page and give it a few moments to update. Reload the ASDM page and it should be working now.

  1. Jon Schwartz says:

    DOES NOT WORK, nosecurity.ssl3.rsa_des_sha LISTED IN SETTINGS