CVE-2018-12232

Published: 12 June 2018

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).

Priority

Cvss 3 Severity Score

5.9

Score breakdown

Status

Package	Release	Status
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	Not vulnerable
	upstream	Released (4.18~rc1)
	xenial	Not vulnerable
	Patches: Introduced by 86741ec25462e4c8cdce6df2f41ead05568c7d5e Fixed by 6d8c50dcb029872b298eea68cc6209c866fd3e14
linux-aws Launchpad, Ubuntu, Debian	artful	Does not exist
	bionic	Released (4.15.0-1020.20)
	cosmic	Not vulnerable (4.15.0-1020.20)
	trusty	Not vulnerable
	upstream	Released (4.18~rc1)
	xenial	Not vulnerable
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~rc1)
	xenial	Released (4.15.0-1022.22~16.04.1)
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~rc1)
	xenial	Released (4.15.0-1022.23)
linux-euclid Launchpad, Ubuntu, Debian	artful	Does not exist
	bionic	Does not exist
	cosmic	Does not exist
	trusty	Does not exist
	upstream	Released (4.18~rc1)
	xenial	Ignored (was needed ESM criteria)
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~rc1)
	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~rc1)
	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~rc1)
	xenial	Ignored (end of standard support, was needs-triage)
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~rc1)
	xenial	Ignored (end of life, was needs-triage)
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~rc1)
	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~rc1)
	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~rc1)
	xenial	Released (4.15.0-33.36~16.04.1)
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~rc1)
	xenial	Not vulnerable
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~rc1)
	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~rc1)
	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~rc1)
	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~rc1)
	xenial	Does not exist
linux-lts-xenial Launchpad, Ubuntu, Debian	artful	Does not exist
	bionic	Does not exist
	cosmic	Does not exist
	trusty	Not vulnerable
	upstream	Released (4.18~rc1)
	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~rc1)
	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~rc1)
	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~rc1)
	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~rc1)
	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~rc1)
	xenial	Not vulnerable
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~rc1)
	xenial	Not vulnerable

Severity score breakdown

Parameter	Value
Base score	5.9
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

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