Sophos UTM HTTP Proxy Does Not Work On Version 9.5

There is a known issue where Httpproxy with AD-SSO authentication in transparent mode doesn’t work with IE and Chrome after upgrading to Sophos UTM 9.5. Sophos are aware of this.

Resolution:

Upgrade to Sophos UTM 9.5 MR2 (9.502) which has been released and fixed this issue. Then, if possible update to the latest current version.

A domain re-join is necessary for making AD-SSO to work if you update to 9.502 and the appliance was rebooted between 9.501 and 9.502 update:

The re-join can be done following these steps:

1. 1. In the WebAdmin, browse to Definition & Users > Authentication Services > Single Sign-On.
   2. Type the username with incorrect password in the Active Directory Single-Sign-On (SSO) fields.
   3. Click Apply.
   4. Wait for error message in WebAdmin (Joining the domain failed).
      1. On a domain controller, manually delete the UTM’s computer account from AD; sync changes will ALL domain controllers.
   5. Type the username with correct password in the Active Directory Single-Sign-On (SSO) fields.
   6. Wait for error message in WebAdmin (Active Directory SSO saved successfully).

If the appliance has been rebooted between 9.501 installation and 9.502 upgrade, then re-joining will fix Kerberos authentication and ad-sync.

If the appliance has not been rebooted between 9.501 installation and 9.502 upgrade, then re-joining will fix ad-sync. Kerberos authentication would correctly work without re-joining.

The reason for this is that the machine password (that was changed via net ads changetrustpw) is lost during mdw restart.