I'm trying to get Cisco Anyconnect working on a fresh install of Ubuntu 18.04. The vpn I'm connecting to requires 2fa, using Duo Mobile push or a text code. The program connects fine, and I enter my login information and verify the login requires using Duo on my phone, but the gui then hangs with the message "Please complete the authentication process in the AnyConnect Login Window".
On Ubuntu 16.04, authentication of 2fa was followed by a popup window where you had to click "Accept" to finish the connection (see figure 1). It seems that this window is not appearing on 18.04, preventing me from finalizing the connection. Any thoughts on what's going on here?
I had the same problem with AnyConnect Linux64 4.6.00362 on a 18.04 VirtualBox machine with OKTA MFA, but then upgraded the client to 4.6.04056 and the issue went away.
I had the same issue on 18.04 (and Debian Experimental, as it happens). It turns out that our VPN has two access points. One is of the form "vpn.site.com", and using this one gives the "no banner" problem.
But another is of the form "vpn.site.com/mfa". If you use that one, Anyconnect asks for your login information in the GUI rather than opening a separate window. It sends the Duo push automatically. Then the banner will show up normally and the VPN connects.