The Linux kernel before version 5.8 is vulnerable to a NULL pointer dereference in drivers/tty/serial/8250/8250_core.c:serial8250_isa_init_ports() that allows local users to cause a denial of service by using the p->serial_in pointer which uninitialized.
Exploitability
AV:LAC:LPR:HUI:NScope
S:UImpact
C:NI:NA:H4.4/CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H