There is 1 open security issue in bullseye.
1 issue left for the package maintainer to handle:
A flaw was found in Keystone. There is a time lag (up to one hour in a default configuration) between when security policy says a token should be revoked from when it is actually revoked. This could allow a remote administrator to secretly maintain access for longer than expected.
You can find information about how to handle this issue in the security team's documentation.