More information about this security flaw is available in the following bug: https://bugzilla.redhat.com/show_bug.cgi?id=2379554 Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
The jakarta-mail package does build against, nor does it bundle, the apache commons lang java library. There is nothing that can be done on the jakarta-mail side.