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.
Jon, why did you file this report against the pdftk-java RPM package? The security flaw is in the apache-commons-lang3 RPM package, if I am not completely mistaken…