K36462841 : Linux kernel vulnerability CVE-2018-18281

Security Advisory Description

Since Linux kernel version 3.2, the mremap() syscall performs TLB flushes after dropping pagetable locks. If a syscall such as ftruncate() removes entries from the pagetables of a task that is in the middle of mremap(), a stale TLB entry can remain for a short time that permits access to a physical page after it has been released back to the page allocator and reused. This is fixed in the following kernel versions: 4.9.135, 4.14.78, 4.18.16, 4.19. (CVE-2018-18281)

Impact

An attacker may be able to overflow temporary memory resources resulting in improper access to physical memory pages or denial-of-service (DoS).