Vulnerability Description
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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | < 4.19.7 |
| Redhat | Openshift Container Platform | 3.11 |
| Redhat | Virtualization Host | 4.0 |
| Redhat | Enterprise Linux Desktop | 7.0 |
| Redhat | Enterprise Linux Server | 7.0 |
| Redhat | Enterprise Linux Server Aus | 7.4 |
| Redhat | Enterprise Linux Server Eus | 7.4 |
| Redhat | Enterprise Linux Server Tus | 7.4 |
| Redhat | Enterprise Linux Workstation | 7.0 |
| Canonical | Ubuntu Linux | 14.04 |
Related Weaknesses (CWE)
References
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=29ec90PatchThird Party Advisory
- https://access.redhat.com/errata/RHBA-2019:0327Third Party Advisory
- https://access.redhat.com/errata/RHSA-2019:0163Third Party Advisory
- https://access.redhat.com/errata/RHSA-2019:0202Third Party Advisory
- https://access.redhat.com/errata/RHSA-2019:0324Third Party Advisory
- https://access.redhat.com/errata/RHSA-2019:0831Third Party Advisory
- https://bugs.chromium.org/p/project-zero/issues/detail?id=1700ExploitIssue TrackingThird Party Advisory
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.87PatchVendor Advisory
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.7PatchVendor Advisory
- https://github.com/torvalds/linux/commit/29ec90660d68bbdd69507c1c8b4e33aa299278bPatchThird Party Advisory
- https://usn.ubuntu.com/3901-1/Third Party Advisory
- https://usn.ubuntu.com/3901-2/Third Party Advisory
- https://usn.ubuntu.com/3903-1/Third Party Advisory
- https://usn.ubuntu.com/3903-2/Third Party Advisory
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=29ec90PatchThird Party Advisory
FAQ
What is CVE-2018-18397?
CVE-2018-18397 is a vulnerability with a CVSS score of 5.5 (MEDIUM). 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 ...
How severe is CVE-2018-18397?
CVE-2018-18397 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2018-18397?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel, Redhat Openshift Container Platform, Redhat Virtualization Host, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Server.