Authentication failed due to problem verifying server certificate

[optytrex]

Installed Ubuntu in VMware and installed Cisco Anyconnect but it gives me the above message even when I deselect "Block connections to untrusted servers"

The SMAL connection window pops up after a second and then within a couple of seconds, it closes out without ever displaying anything and gives me the message in the title. Nothing else. 

Any idea what I could do to establish a connection? I've tried other VPNs (all known good) and I can't connect to them. I've heard I might need to install certificates but haven't done that anywhere else so not sure what I'm doing wrong. Any help is appreciated.

Thanks.

[Kasun Bandara]

check if these are helps ...

https://community.cisco.com/t5/vpn/anyconnect-linux-4-8-authentication-failed/td-p/4127671

https://www.reddit.com/r/linuxmint/comments/gu5jd8/vpn_client_no_longer_connects_to_server_looking/

[optytrex]

I will check this and report back. Thanks for the help!

[balaji.bandi]

is your environment have certificate-based authentication? how is your windows client authenticated?

[optytrex]

We use SAML authentication and have used this functionality in a Windows environment with many users but have just begun testing in Ubuntu. 

[123456789ali]

close the cisco vpn application 

download the application from the source 

sudo bash <AnyconnectFile.sh>

sudo apt update

sudo apt install -y libwebkit2gtk-4.0-37

sudo apt update

ADDRESS=<write your IP or Domain>

echo | openssl s_client ${ADDRESS}:443 | openssl x509 > ${ADDRESS}.crt

cp TheCertificateFromabove.crt  /usr/local/share/ca-certificates/

sudo update-ca-certificates

sudo apt update 

/opt/cisco/secureclient/bin/vpnui

this is helped me with ubuntu 22.4 and cisco secure client 5.0.05040