Bug 1283279 (CVE-2015-7496)

Summary:	CVE-2015-7496 gdm: Crash when holding Escape in log screen
Product:	[Other] Security Response	Reporter:	Adam Mariš <amaris>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	carnil, rstrode
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	gdm 3.19.2	Doc Type:	Bug Fix
Doc Text:	It was found that gdm could crash due to a signal handler dispatched to an invalid conversation. An attacker could crash gdm by holding the escape key when the screen is locked, possibly bypassing the locked screen.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2017-08-03 08:40:54 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1283281
Bug Blocks:	1283283

Description Adam Mariš 2015-11-18 15:21:21 UTC

It was found that when running gnome session, user locks the machine (by pressing <super> + l), presses Escape and holds, gdm will crash causing segmentation fault.

Upstream bug:

https://bugzilla.gnome.org/show_bug.cgi?id=758032

Upstream patches:

https://git.gnome.org/browse/gdm/commit/?id=5ac2246
https://git.gnome.org/browse/gdm/commit/?id=05e5fc2

Comment 1 Adam Mariš 2015-11-18 15:21:37 UTC

Created gdm tracking bugs for this issue:

Affects: fedora-all [bug 1283281]

Comment 2 Fedora Update System 2015-11-22 02:23:00 UTC

gdm-3.18.2-1.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.

Comment 3 errata-xmlrpc 2017-08-01 22:59:25 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2017:2128 https://access.redhat.com/errata/RHSA-2017:2128