CVE-2015-8316

Publication date 6 September 2017

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

Array index error in LightDM (aka Light Display Manager) 1.14.3, 1.16.x before 1.16.6 when the XDMCP server is enabled allows remote attackers to cause a denial of service (process crash) via an XDMCP request packet with no address.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
lightdm	16.04 LTS xenial	Not affected
	15.10 wily	Ignored end of life
	15.04 vivid	Not affected
	14.04 LTS trusty	Not in release
	12.04 LTS precise	Not affected

Notes

mdeslaur

introduced in 1.14.3 and 1.15.1 by the following commits: http://bazaar.launchpad.net/~lightdm-team/lightdm/1.14/revision/2143 http://bazaar.launchpad.net/~lightdm-team/lightdm/1.16/revision/2155 fixed in 1.14.4, 1.16.6 and 1.17.2

Patch details

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

Package	Patch details
lightdm	Upstream: https://bazaar.launchpad.net/~lightdm-team/lightdm/1.14/revision/2166 Upstream: https://bazaar.launchpad.net/~lightdm-team/lightdm/1.16/revision/2207

Severity score breakdown

CVSS version: CVSS v3.0

Base score 5.9 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	High
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality impact	None
Integrity impact	None
Availability impact	High

Scores

Parameter	Value
Base score	5.9 · Medium
Exploitability score	-
Impact score	-

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H