CVE-2018-13405
Published: 6 July 2018
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.
From the Ubuntu Security Team
It was discovered that the Linux kernel did not properly handle setgid file creation when performed by a non-member of the group. A local attacker could use this to gain elevated privileges.
Notes
Author | Note |
---|---|
tyhicks | While inode_init_owner() has only been vulnerable since its introduction in a1bd120d13e586ea1c424048fd2c8420a442852a, this flaw has been present in individual filesystems since the beginning of the kernel git history. |
Priority
Status
Package | Release | Status |
---|---|---|
linux-aws Launchpad, Ubuntu, Debian |
upstream |
Released
(4.18~rc4)
|
trusty |
Released
(4.4.0-1028.31)
|
|
xenial |
Released
(4.4.0-1066.76)
|
|
artful |
Does not exist
|
|
bionic |
Released
(4.15.0-1020.20)
|
|
cosmic |
Not vulnerable
(4.15.0-1020.20)
|
|
linux-azure Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Released
(4.15.0-1022.23)
|
|
cosmic |
Not vulnerable
(4.18.0-1003.3)
|
|
trusty |
Not vulnerable
(4.15.0-1023.24~14.04.1)
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Released
(4.15.0-1022.22~16.04.1)
|
|
linux-kvm Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Released
(4.15.0-1020.20)
|
|
cosmic |
Not vulnerable
(4.15.0-1020.20)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Released
(4.4.0-1032.38)
|
|
linux-euclid Launchpad, Ubuntu, Debian |
upstream |
Released
(4.18~rc4)
|
trusty |
Does not exist
|
|
xenial |
Ignored
(was needed ESM criteria)
|
|
artful |
Does not exist
|
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
linux Launchpad, Ubuntu, Debian |
artful |
Ignored
(end of life)
|
bionic |
Released
(4.15.0-33.36)
|
|
cosmic |
Not vulnerable
(4.17.0-6.7)
|
|
trusty |
Released
(3.13.0-157.207)
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Released
(4.4.0-134.160)
|
|
Patches: Introduced by 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 |
||
linux-azure-edge Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Not vulnerable
(4.18.0-1003.3~18.04.1)
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Released
(4.15.0-1022.23)
|
|
linux-flo Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
(trusty was ignored [abandoned])
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Ignored
(abandoned)
|
|
linux-gcp Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Released
(4.15.0-1018.19)
|
|
cosmic |
Not vulnerable
(4.15.0-1018.19)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Released
(4.15.0-1018.19~16.04.2)
|
|
linux-gke Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Ignored
(end of standard support)
|
|
linux-goldfish Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
(trusty was ignored [abandoned])
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Ignored
(end of life)
|
|
linux-grouper Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
(trusty was ignored [abandoned])
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Does not exist
|
|
linux-hwe Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Not vulnerable
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Released
(4.15.0-33.36~16.04.1)
|
|
linux-hwe-edge Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Not vulnerable
(4.18.0-11.12~18.04.1)
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Released
(4.15.0-33.36~16.04.1)
|
|
linux-lts-trusty Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Does not exist
|
|
linux-lts-utopic Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
(trusty was ignored [end of standard support])
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Does not exist
|
|
linux-lts-vivid Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
(trusty was ignored [end of standard support])
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Does not exist
|
|
linux-lts-wily Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
(trusty was ignored [end of standard support])
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Does not exist
|
|
linux-lts-xenial Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
trusty |
Released
(4.4.0-134.160~14.04.1)
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Does not exist
|
|
linux-maguro Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
(trusty was ignored [abandoned])
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Does not exist
|
|
linux-mako Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
(trusty was ignored [abandoned])
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Ignored
(abandoned)
|
|
linux-manta Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Does not exist
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
(trusty was ignored [abandoned])
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Does not exist
|
|
linux-oem Launchpad, Ubuntu, Debian |
artful |
Does not exist
|
bionic |
Released
(4.15.0-1017.20)
|
|
cosmic |
Not vulnerable
(4.15.0-1017.20)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Ignored
(end of standard support, was needed)
|
|
linux-raspi2 Launchpad, Ubuntu, Debian |
artful |
Ignored
(end of life)
|
bionic |
Released
(4.15.0-1021.23)
|
|
cosmic |
Not vulnerable
(4.15.0-1021.23)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Released
(4.4.0-1095.103)
|
|
linux-snapdragon Launchpad, Ubuntu, Debian |
artful |
Ignored
(end of life)
|
bionic |
Not vulnerable
|
|
cosmic |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(4.18~rc4)
|
|
xenial |
Released
(4.4.0-1099.104)
|
Severity score breakdown
Parameter | Value |
---|---|
Base score | 7.8 |
Attack vector | Local |
Attack complexity | Low |
Privileges required | Low |
User interaction | None |
Scope | Unchanged |
Confidentiality | High |
Integrity impact | High |
Availability impact | High |
Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
References
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-13405
- https://git.kernel.org/linux/0fa3ecd87848c9c93c2c828ef4c3a8ca36ce46c7
- https://twitter.com/grsecurity/status/1015082951204327425
- https://www.halfdog.net/Security/2015/SetgidDirectoryPrivilegeEscalation/
- https://ubuntu.com/security/notices/USN-3752-1
- https://ubuntu.com/security/notices/USN-3752-2
- https://ubuntu.com/security/notices/USN-3753-1
- https://ubuntu.com/security/notices/USN-3753-2
- https://ubuntu.com/security/notices/USN-3754-1
- https://ubuntu.com/security/notices/USN-3752-3
- NVD
- Launchpad
- Debian