The sanity_check_ckpt function in fs/f2fs/super.c in the Linux kernel before 4.12.4 does not validate the blkoff and segno arrays, which allows local users to gain privileges via unspecified vectors.
http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.12.4
http://www.securityfocus.com/bid/100215
https://bugzilla.redhat.com/show_bug.cgi?id=1481149
https://github.com/torvalds/linux/commit/15d3042a937c13f5d9244241c7a9c8416ff6e82a
Source: MITRE
Published: 2017-08-19
Updated: 2017-08-23
Type: CWE-129
Base Score: 7.2
Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C
Impact Score: 10
Exploitability Score: 3.9
Severity: HIGH
Base Score: 7.8
Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 1.8
Severity: HIGH