kernel is vulnerable to use-after-free. It is possible due to a flaw in ext4_put_super.
lists.opensuse.org/opensuse-security-announce/2020-03/msg00021.html
access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/8.3_release_notes/index
access.redhat.com/errata/RHSA-2020:4609
access.redhat.com/security/updates/classification/#moderate
github.com/bobfuzzer/CVE/tree/master/CVE-2019-19447
lists.debian.org/debian-lts-announce/2020/03/msg00001.html
lists.debian.org/debian-lts-announce/2020/06/msg00011.html
lists.debian.org/debian-lts-announce/2020/06/msg00013.html
security.netapp.com/advisory/ntap-20200103-0001/