Bug 867908 (CVE-2012-4524)

Summary: CVE-2012-4524 xlockmore: Screensaver crash (screen lock bypass) when 'dclock' mode used
Product: [Other] Security Response Reporter: Jan Lieskovsky <jlieskov>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: adrian
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2013-05-08 17:35:01 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On: 867910, 867911    
Bug Blocks:    
Description Flags
Local copy of the proposed preliminary patch from [1] none

Description Jan Lieskovsky 2012-10-18 14:36:25 UTC
A denial of service flaw was found in the way xlockmore, X screen lock and screen saver, performed passing arguments to underlying localtime() call, when the 'dlock' mode was used. An attacker could use this flaw to potentially obtain unauthorized access to screen / graphical session, previously locked by another user / victim.

CVE request (containing also patch proposal):
[1] http://www.openwall.com/lists/oss-security/2012/10/17/10

Comment 1 Jan Lieskovsky 2012-10-18 14:39:58 UTC
Created attachment 629482 [details]
Local copy of the proposed preliminary patch from [1]

Comment 2 Jan Lieskovsky 2012-10-18 14:41:06 UTC
This issue affects the versions of the xlockmore package, as shipped with Fedora release of 16 and 17. Please schedule an update.


This issue affects the version of the xlockmore package, as shipped with Fedora EPEL 6. Please schedule an update.

Comment 3 Jan Lieskovsky 2012-10-18 14:42:42 UTC
Created xlockmore tracking bugs for this issue

Affects: fedora-all [bug 867910]
Affects: epel-6 [bug 867911]

Comment 4 Fedora Update System 2012-11-20 19:40:33 UTC
xlockmore-5.40-4.el6 has been pushed to the Fedora EPEL 6 stable repository.  If problems still persist, please make note of it in this bug report.