CVE-2018-13405high
Description
The inode_init_owner function in fs/inode.c in the Linux kernel through 3.16 allows local users to create files with an unintended group ownership, in a scenario where a directory is SGID to a certain group and is writable by a user who is not a member of that group. Here, the non-member can trigger creation of a plain file whose group ownership is that group. The intended behavior was that the non-member can trigger creation of a directory (but not a plain file) whose group ownership is that group. The non-member can escalate privileges by making the plain file executable and SGID.
References
https://twitter.com/grsecurity/status/1015082951204327425
https://github.com/torvalds/linux/commit/0fa3ecd87848c9c93c2c828ef4c3a8ca36ce46c7
http://openwall.com/lists/oss-security/2018/07/13/2
https://www.exploit-db.com/exploits/45033/
https://www.debian.org/security/2018/dsa-4266
https://lists.debian.org/debian-lts-announce/2018/08/msg00014.html
https://usn.ubuntu.com/3754-1/
https://usn.ubuntu.com/3753-2/
https://usn.ubuntu.com/3753-1/
https://usn.ubuntu.com/3752-2/
https://usn.ubuntu.com/3752-1/
https://usn.ubuntu.com/3752-3/
https://access.redhat.com/errata/RHSA-2018:3096
https://access.redhat.com/errata/RHSA-2018:3083
https://access.redhat.com/errata/RHSA-2018:2948
http://www.securityfocus.com/bid/106503
https://access.redhat.com/errata/RHSA-2019:0717
https://support.f5.com/csp/article/K00854051
https://access.redhat.com/errata/RHSA-2019:2476
https://access.redhat.com/errata/RHSA-2019:2566
https://access.redhat.com/errata/RHSA-2019:2696
https://access.redhat.com/errata/RHSA-2019:2730
https://access.redhat.com/errata/RHSA-2019:4164
Details
Source: MITRE
Published: 2018-07-06
Updated: 2022-04-06
Type: CWE-269
Risk Information
CVSS v2
Base Score: 4.6
Vector: AV:L/AC:L/Au:N/C:P/I:P/A:P
Impact Score: 6.4
Exploitability Score: 3.9
Severity: MEDIUM
CVSS v3
Base Score: 7.8
Vector: CVSS:3.1/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