Vulnerability Details : CVE-2018-18397
The userfaultfd implementation in the Linux kernel before 4.19.7 mishandles access control for certain UFFDIO_ ioctl calls, as demonstrated by allowing local users to write data into holes in a tmpfs file (if the user has read-only access to that file, and that file contains holes), related to fs/userfaultfd.c and mm/userfaultfd.c.
Exploit prediction scoring system (EPSS) score for CVE-2018-18397
Probability of exploitation activity in the next 30 days: 0.04%
Percentile, the proportion of vulnerabilities that are scored at or less: ~ 8 % EPSS Score History EPSS FAQ
CVSS scores for CVE-2018-18397
Base Score | Base Severity | CVSS Vector | Exploitability Score | Impact Score | Score Source |
---|---|---|---|---|---|
2.1
|
LOW | AV:L/AC:L/Au:N/C:N/I:P/A:N |
3.9
|
2.9
|
NIST |
5.5
|
MEDIUM | CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
1.8
|
3.6
|
NIST |
CWE ids for CVE-2018-18397
-
The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions.Assigned by: nvd@nist.gov (Primary)
References for CVE-2018-18397
-
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.87
Patch;Vendor Advisory
-
https://access.redhat.com/errata/RHSA-2019:0163
RHSA-2019:0163 - Security Advisory - Red Hat Customer PortalThird Party Advisory
-
https://usn.ubuntu.com/3901-2/
USN-3901-2: Linux kernel (HWE) vulnerabilities | Ubuntu security noticesThird Party Advisory
-
https://access.redhat.com/errata/RHBA-2019:0327
RHBA-2019:0327 - Bug Fix Advisory - Red Hat Customer PortalThird Party Advisory
-
https://access.redhat.com/errata/RHSA-2019:0324
RHSA-2019:0324 - Security Advisory - Red Hat Customer PortalThird Party Advisory
-
https://usn.ubuntu.com/3901-1/
USN-3901-1: Linux kernel vulnerabilities | Ubuntu security noticesThird Party Advisory
-
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=29ec90660d68bbdd69507c1c8b4e33aa299278b1
kernel/git/torvalds/linux.git - Linux kernel source treePatch;Third Party Advisory
-
https://github.com/torvalds/linux/commit/29ec90660d68bbdd69507c1c8b4e33aa299278b1
userfaultfd: shmem/hugetlbfs: only allow to register VM_MAYWRITE vmas · torvalds/linux@29ec906 · GitHubPatch;Third Party Advisory
-
https://usn.ubuntu.com/3903-1/
USN-3903-1: Linux kernel vulnerabilities | Ubuntu security noticesThird Party Advisory
-
https://access.redhat.com/errata/RHSA-2019:0202
RHSA-2019:0202 - Security Advisory - Red Hat Customer PortalThird Party Advisory
-
https://access.redhat.com/errata/RHSA-2019:0831
RHSA-2019:0831 - Security Advisory - Red Hat Customer PortalThird Party Advisory
-
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.7
Patch;Vendor Advisory
-
https://bugs.chromium.org/p/project-zero/issues/detail?id=1700
1700 - Linux: userfaultfd bypasses tmpfs file permissions - project-zero - MonorailExploit;Issue Tracking;Third Party Advisory
-
https://usn.ubuntu.com/3903-2/
USN-3903-2: Linux kernel (HWE) vulnerabilities | Ubuntu security noticesThird Party Advisory
Products affected by CVE-2018-18397
- cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_aus:7.4:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_eus:7.4:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_eus:7.6:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_eus:7.5:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_tus:7.4:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:virtualization_host:4.0:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:openshift_container_platform:3.11:*:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*