This package uses eclasses which were vulnerable to root privilege escalation via "chown", see bug 630822 for details. The eclasses were fixed, however a rev bump is required to ensure that the vulnerability is completely removed.
The bug has been referenced in the following commit(s):
Author: Thomas Deutschmann <email@example.com>
AuthorDate: 2017-10-28 18:10:07 +0000
Commit: Thomas Deutschmann <firstname.lastname@example.org>
CommitDate: 2017-10-28 18:10:57 +0000
dev-db/mysql-cluster: Rev bump to fix CVE-2017-15945
Package-Manager: Portage-2.3.13, Repoman-2.3.4
.../mysql-cluster/mysql-cluster-7.2.22-r1.ebuild | 124 ++++++++++++++++++
.../mysql-cluster/mysql-cluster-7.3.11-r1.ebuild | 143 +++++++++++++++++++++
2 files changed, 267 insertions(+)}
All done, repository is clean.