The __get_user_asm_ex macro in arch/x86/include/asm/uaccess.h in the Linux kernel 4.4.22 through 4.4.28 contains extended asm statements that are incompatible with the exception table, which allows local users to obtain root access on non-SMEP platforms via a crafted application. NOTE: this vulnerability exists because of incorrect backporting of the CVE-2016-9178 patch to older kernels.
Exploitability
AV:LAC:LPR:NUI:RScope
S:UImpact
C:HI:HA:H7.8/CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H