Detections
Analytics
CVE-2018-18281
high
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.
References
https://usn.ubuntu.com/3880-2/
https://usn.ubuntu.com/3880-1/
https://usn.ubuntu.com/3871-5/
https://usn.ubuntu.com/3871-4/
https://usn.ubuntu.com/3871-3/
https://usn.ubuntu.com/3871-1/
https://usn.ubuntu.com/3835-1/
https://usn.ubuntu.com/3832-1/
https://lists.debian.org/debian-lts-announce/2019/04/msg00004.html
https://lists.debian.org/debian-lts-announce/2019/03/msg00034.html
https://lists.debian.org/debian-lts-announce/2019/03/msg00017.html
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.135
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.18.16
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.78
https://access.redhat.com/errata/RHSA-2020:0179
https://access.redhat.com/errata/RHSA-2020:0103
https://access.redhat.com/errata/RHSA-2020:0100
https://access.redhat.com/errata/RHSA-2020:0036
https://access.redhat.com/errata/RHSA-2019:2043
https://access.redhat.com/errata/RHSA-2019:2029
https://access.redhat.com/errata/RHSA-2019:0831
http://www.securityfocus.com/bid/106503
http://www.securityfocus.com/bid/105761
http://www.openwall.com/lists/oss-security/2018/10/29/5
http://packetstormsecurity.com/files/150001/Linux-mremap-TLB-Flush-Too-Late.html