The Linux kernel 4.9.x before 4.9.233, 4.14.x before 4.14.194, and 4.19.x before 4.19.140 has a use-after-free because skcd->no_refcnt was not considered during a backport of a CVE-2020-14356 patch. This is related to the cgroups feature.
Source: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-25220
Reference (s):
- https://security.netapp.com/advisory/ntap-20201001-0004/
- https://bugzilla.redhat.com/show_bug.cgi?id=1868453
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.194
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.140
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.233