Luke Taylor (Migrated from SEC-1476) said:
The unsuccessfulAuthentication() method currently creates a session to store the failure exception. This shouldn't be the default. The user can override the behaviour if required. Caching it in the request should be adequate for most authentication failure purposes.
David Balažic said:
This is fixed in this commit: 0c09780
(I stumbled onto this and noticed the commit is not mentioned here)