A flaw was found in the Linux kernel present since v4.0-rc1 and through v4.13-rc4. A crafted network packet sent remotely by an attacker may force the kernel to enter an infinite loop in the cipso_v4_optptr() function in net/ipv4/cipso_ipv4.c leading to a denial-of-service. A certain non-default configuration of LSM (Linux Security Module) and NetLabel should be set up on a system before an attacker could leverage this flaw.

net/ipv4/route.c in the Linux kernel 4.13-rc1 through 4.13-rc6 is too late to check for a NULL fi field when RTM_F_FIB_MATCH is set, which allows local users to cause a denial of service (NULL pointer dereference) or possibly have unspecified other impact via crafted system calls. NOTE: this does not affect any stable release.

The pit_ioport_read in i8254.c in the Linux kernel before 2.6.33 and QEMU before 2.3.1 does not distinguish between read lengths and write lengths, which might allow guest OS users to execute arbitrary code on the host OS by triggering use of an invalid index.