There is 1 open security issue in buster.
1 issue left for the package maintainer to handle:
Improper validation of certificate with host mismatch in Apache Log4j SMTP appender. This could allow an SMTPS connection to be intercepted by a man-in-the-middle attack which could leak any log messages sent through that appender.
You can find information about how to handle this issue in the security team's documentation.