In FreeBSD 13.0-STABLE before n245118, 12.2-STABLE before r369552, 11.4-STABLE before r369560, 13.0-RC5 before p1, 12.2-RELEASE before p6, and 11.4-RELEASE before p9, a superuser inside a FreeBSD jail configured with the non-default allow.mount permission could cause a race condition between the lookup of “..” and remounting a filesystem, allowing access to filesystem hierarchy outside of the jail.
Source: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-25584
Reference (s):
- https://security.netapp.com/advisory/ntap-20210423-0009/
- https://security.FreeBSD.org/advisories/FreeBSD-SA-21:10.jail_mount.asc
- URL: https://security.FreeBSD.org/advisories/FreeBSD-SA-21:10.jail_mount.asc