CVE-2018-12232

Publication date 12 June 2018

Last updated 25 August 2025

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

5.9 · Medium

Score breakdown

Description

In net/socket.c in the Linux kernel through 4.17.1, there is a race condition between fchownat and close in cases where they target the same socket file descriptor, related to the sock_close and sockfs_setattr functions. fchownat does not increment the file descriptor reference count, which allows close to set the socket to NULL during fchownat's execution, leading to a NULL pointer dereference and system crash.

From the Ubuntu Security Team

Shankara Pailoor discovered that a race condition existed in the socket handling code in the Linux kernel. A local attacker could use this to cause a denial of service (system crash).

Status

Package Ubuntu Release Status
linux 18.10 cosmic
Not affected
18.04 LTS bionic
Fixed 4.15.0-33.36
17.10 artful Ignored end of life
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected
linux-aws 18.10 cosmic
Not affected
18.04 LTS bionic
Fixed 4.15.0-1020.20
17.10 artful Not in release
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected
linux-azure 18.10 cosmic
Not affected
18.04 LTS bionic
Fixed 4.15.0-1022.23
17.10 artful Not in release
16.04 LTS xenial
Fixed 4.15.0-1022.22~16.04.1
14.04 LTS trusty
Not affected
linux-azure-edge 18.10 cosmic Not in release
18.04 LTS bionic
Not affected
17.10 artful Not in release
16.04 LTS xenial
Fixed 4.15.0-1022.23
14.04 LTS trusty Not in release
linux-euclid 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-kvm 18.10 cosmic
Not affected
18.04 LTS bionic
Fixed 4.15.0-1020.20
17.10 artful Not in release
16.04 LTS xenial
Not affected
14.04 LTS trusty Not in release
linux-oem 18.10 cosmic
Not affected
18.04 LTS bionic
Fixed 4.15.0-1017.20
17.10 artful Not in release
16.04 LTS xenial Ignored end of standard support, was needed
14.04 LTS trusty Not in release
linux-flo 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-goldfish 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-hwe 18.10 cosmic Not in release
18.04 LTS bionic
Not affected
17.10 artful Not in release
16.04 LTS xenial
Fixed 4.15.0-33.36~16.04.1
14.04 LTS trusty Not in release
linux-hwe-edge 18.10 cosmic Not in release
18.04 LTS bionic
Not affected
17.10 artful Not in release
16.04 LTS xenial
Fixed 4.15.0-33.36~16.04.1
14.04 LTS trusty Not in release
linux-gcp 18.10 cosmic
Not affected
18.04 LTS bionic
Fixed 4.15.0-1018.19
17.10 artful Not in release
16.04 LTS xenial
Fixed 4.15.0-1018.19~16.04.2
14.04 LTS trusty Not in release
linux-gke 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Ignored end of standard support, was needs-triage
14.04 LTS trusty Not in release
linux-grouper 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-lts-trusty 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-lts-utopic 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-lts-vivid 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-lts-wily 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-lts-xenial 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty
Not affected
linux-maguro 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-mako 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-manta 18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
linux-raspi2 18.10 cosmic
Not affected
18.04 LTS bionic
Fixed 4.15.0-1021.23
17.10 artful Ignored end of life
16.04 LTS xenial
Not affected
14.04 LTS trusty Not in release
linux-snapdragon 18.10 cosmic Not in release
18.04 LTS bionic
Not affected
17.10 artful Ignored end of life
16.04 LTS xenial
Not affected
14.04 LTS trusty Not in release

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
linux

Severity score breakdown

Parameter Value
Base score 5.9 · Medium
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact High
Vector CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

    • USN-3752-2
    • Linux kernel (HWE) vulnerabilities
    • 24 August 2018
    • USN-3752-1
    • Linux kernel vulnerabilities
    • 24 August 2018
    • USN-3752-3
    • Linux kernel (Azure, GCP, OEM) vulnerabilities
    • 28 August 2018

Other references