A vulnerability was found in perl. The regex engine got into an infinite loop because of the malformation. It is trying to back-up over a sequence of UTF-8 continuation bytes. The character just before the sequence should be a start byte. If it's not, there is a malformation which results in "hang" of regexp matching and CPU exhaustion.
Created perl tracking bugs for this issue:
Affects: fedora-22 [bug 1329107]
Red Hat Product Security has rated this issue as having Moderate security impact. This issue is not currently planned to be addressed in future updates. For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/.
perl-5.20.3-330.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.