While testing the bad password lockout I discovered that univention-s4search -Utestuser%wrongpassword increases the badPwdCount by 2. If "-k no" is given, the badPwdCount only increases by 1. I think we may better default to this setting to avoid the additional Kerberos operation. From diffing the logs it looks like this also reduces the steps performed during a successful authorization. This new default can then be overridden by appending a "-k yes" on the commandline.
See https://forge.univention.org/bugzilla/show_bug.cgi?id=41835#c1 for a possible fix.
This issue has been filed against UCS 4.4. UCS 4.4 is out of maintenance and components may have vastly changed in later releases. Thus, this issue is now being closed. If this issue still occurs in newer versions, please use "Clone this bug" or reopen this issue. In this case please provide information on how this issue is affecting you.