In FreeBSD 12.1-STABLE before r360971, 12.1-RELEASE before p5, 11.4-STABLE before r360971, 11.4-BETA1 before p1 and 11.3-RELEASE before p9, libalias does not properly validate packet length resulting in modules causing an out of bounds read/write condition if no checking was built into the module.
https://www.zerodayinitiative.com/advisories/ZDI-20-660/
https://www.zerodayinitiative.com/advisories/ZDI-20-659/
https://security.netapp.com/advisory/ntap-20200518-0005/
https://security.FreeBSD.org/advisories/FreeBSD-SA-20:12.libalias.asc