Detections
Analytics
CVE-2018-18397
medium
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.
References
https://usn.ubuntu.com/3903-2/
https://usn.ubuntu.com/3903-1/
https://usn.ubuntu.com/3901-2/
https://usn.ubuntu.com/3901-1/
https://github.com/torvalds/linux/commit/29ec90660d68bbdd69507c1c8b4e33aa299278b1
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.7
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.87
https://bugs.chromium.org/p/project-zero/issues/detail?id=1700
https://access.redhat.com/errata/RHSA-2019:0831
https://access.redhat.com/errata/RHSA-2019:0324
https://access.redhat.com/errata/RHSA-2019:0202
https://access.redhat.com/errata/RHSA-2019:0163