CVE-2018-18281
What it is
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.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 1.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 1.1% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 1.1% · EPSS, next 30 days
- Weakness
- CWE-459
- Record status
- Modified
Affected
- Linux Kernel < 4.9.135
- Linux Kernel < 4.14.78
- Linux Kernel < 4.18.16
- Linux Kernel < 4.19
- Canonical Ubuntu Linux 12.04
- Canonical Ubuntu Linux 14.04
- Canonical Ubuntu Linux 16.04
- Canonical Ubuntu Linux 18.04
Attack profile CVSS 3.0 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2018-18281.md and follow it. Check whether this project is affected by CVE-2018-18281. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- http://packetstormsecurity.com/files/150001/Linux-mremap-TLB-Flush-Too-Late.html
- http://www.openwall.com/lists/oss-security/2018/10/29/5
- https://bugs.chromium.org/p/project-zero/issues/detail?id=1695
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.78
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.18.16
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.135
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=eb66ae030829605d61fbef1909ce310e29f78821
- http://packetstormsecurity.com/files/150001/Linux-mremap-TLB-Flush-Too-Late.html
- http://www.openwall.com/lists/oss-security/2018/10/29/5
- https://bugs.chromium.org/p/project-zero/issues/detail?id=1695
References
- http://packetstormsecurity.com/files/150001/Linux-mremap-TLB-Flush-Too-Late.html
- http://www.openwall.com/lists/oss-security/2018/10/29/5
- http://www.securityfocus.com/bid/105761
- http://www.securityfocus.com/bid/106503
- https://access.redhat.com/errata/RHSA-2019:0831
- https://access.redhat.com/errata/RHSA-2019:2029
- https://access.redhat.com/errata/RHSA-2019:2043
- https://access.redhat.com/errata/RHSA-2020:0036
- https://access.redhat.com/errata/RHSA-2020:0100
- https://access.redhat.com/errata/RHSA-2020:0103
- https://access.redhat.com/errata/RHSA-2020:0179
- https://bugs.chromium.org/p/project-zero/issues/detail?id=1695
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.78
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.18.16
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.135
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=eb66ae030829605d61fbef1909ce310e29f78821
- https://lists.debian.org/debian-lts-announce/2019/03/msg00017.html
- https://lists.debian.org/debian-lts-announce/2019/03/msg00034.html
- https://lists.debian.org/debian-lts-announce/2019/04/msg00004.html
- https://usn.ubuntu.com/3832-1/
- https://usn.ubuntu.com/3835-1/
- https://usn.ubuntu.com/3871-1/
- https://usn.ubuntu.com/3871-3/
- https://usn.ubuntu.com/3871-4/
- https://usn.ubuntu.com/3871-5/