CVE-2017-18018

Publication date 4 January 2018

Last updated 24 July 2024

Ubuntu priority

Cvss 3 Severity Score

In GNU Coreutils through 8.29, chown-core.c in chown and chgrp does not prevent replacement of a plain file with a symlink during use of the POSIX "-R -L" options, which allows local users to modify the ownership of arbitrary files by leveraging a race condition.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
coreutils	22.04 LTS jammy	Not affected
	21.10 impish	Not affected
	21.04 hirsute	Ignored end of life
	20.10 groovy	Ignored end of life
	20.04 LTS focal	Not affected
	19.10 eoan	Ignored end of life
	19.04 disco	Ignored end of life
	18.10 cosmic	Ignored end of life
	18.04 LTS bionic	Ignored documentation patch only
	17.10 artful	Ignored end of life
	17.04 zesty	Ignored end of life
	16.04 LTS xenial	Ignored documentation patch only
	14.04 LTS trusty	Ignored end of ESM support, was ignored [documentation patch only]

Notes

ccdm94

It seems like this will not be fixed upstream (due to the nature of the chown and chgrp utilities), the available patch being a documentation change to warn users about insecure software behavior when certain options are used together in chown and chgrp. For this reason, we will not be fixing this issue in releases where it would be needed. These will be marked as ignored.

Severity score breakdown

Parameter	Value
Base score	4.7 · Medium
Attack vector	Local
Attack complexity	High
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	High
Availability impact	None
Vector	CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N