Cisco ASDM gives “Missing required Permissions manifest attribute in main jar” Error

Java pushed out a new update recently that implemented a change that had been warned about for a while. by default it now no longer allows running apps that are unsigned, self-signed, or without permission attributes.

This includes Cisco ASDM manager. The quick fix (other than Cisco adding the missing permission attributes file) is to add the web address where ASDM is accessed as an exception. You can do do this in Java Settings control panel. This is reached under Window by the Java option under Control Panel.

There select the Security tab and click the Edit Site List… button next to the Exception Site List. Here add the URL to the firewalls that you access with ASDM. After doing this, ASDM will connect and work again normally.

Interestingly enough given Java’s sudden concern about my security, it still asks to install the Ask Toolbar every update….

More info on the change at

13 thoughts on “Cisco ASDM gives “Missing required Permissions manifest attribute in main jar” Error”

  1. Thanks for this Bill. Saved me a lot of time troubleshooting. Receiving an error while trying to log in to your ASDM will definitely send a shiver down your spine…

  2. Excellent write-up.
    Clear, Crisp and To-the-point.
    I hope all technical articles are written in a similar manner and format.

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