Bug 1115576 (CVE-2014-3537) - CVE-2014-3537 cups: insufficient checking leads to privilege escalation
Summary: CVE-2014-3537 cups: insufficient checking leads to privilege escalation
Keywords:
Status: CLOSED ERRATA
Alias: CVE-2014-3537
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
URL:
Whiteboard:
Depends On: 1117794 1118263 1119303
Blocks: 1101912 1115577
TreeView+ depends on / blocked
 
Reported: 2014-07-02 16:07 UTC by Francisco Alonso
Modified: 2023-05-12 13:21 UTC (History)
6 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
It was discovered that CUPS allowed certain users to create symbolic links in certain directories under /var/cache/cups/. A local user with the 'lp' group privileges could use this flaw to read the contents of arbitrary files on the system or, potentially, escalate their privileges on the system.
Clone Of:
Environment:
Last Closed: 2015-03-26 21:43:39 UTC
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
CUPS Bugs and Features 4450 0 None None None Never
Red Hat Product Errata RHSA-2014:1388 0 normal SHIPPED_LIVE Moderate: cups security and bug fix update 2014-10-14 01:21:38 UTC

Description Francisco Alonso 2014-07-02 16:07:26 UTC 
It was discovered that a local user with privileges of group=lp can write symbolic links in the rss directory and use that to gain '@SYSTEM' group privilege with cupsd.

Permissions:

drwxrwxr-x.  2 root lp   4096 Jul  2 09:58 /var/cache/cups/rss

SELinux mitigates this vulnerability
Comment 1 Francisco Alonso 2014-07-02 16:13:27 UTC 
Acknowledgment:

This issue was discovered by Francisco Alonso of the Red Hat Security Response Team.
Comment 7 Francisco Alonso 2014-07-10 09:16:41 UTC 
Statement:

This issue is not planned to be fixed in Red Hat Enterprise Linux 5 as it is now in Production 3 Phase of the support and maintenance life cycle, https://access.redhat.com/support/policy/updates/errata/
Comment 9 Francisco Alonso 2014-07-14 13:19:17 UTC 
Patch for symlink: https://cups.org/strfiles.php/3363/str4450.patch
Fixed In: 2.0-current (SVN: r11993)

References:

http://www.cups.org/blog.php?L724
https://cups.org/str.php?L4450
Comment 10 Francisco Alonso 2014-07-14 13:20:35 UTC 
Created cups tracking bugs for this issue:

Affects: fedora-all [bug 1119303]
Comment 11 Fedora Update System 2014-07-19 06:00:33 UTC 
cups-1.7.4-1.fc20 has been pushed to the Fedora 20 stable repository.  If problems still persist, please make note of it in this bug report.
Comment 14 Francisco Alonso 2014-08-11 14:37:51 UTC 
This fix is insufficient, the additional check can be easily bypassed if language[0] is NULL. The CVE-2014-5029 id has been assigned for the incomplete fix.

http://seclists.org/oss-sec/2014/q3/209
Comment 15 Tomas Hoger 2014-08-11 18:32:53 UTC 
The incomplete fix CVE-2014-5029 is tracked via bug 1122600.
Comment 16 Fedora Update System 2014-10-03 03:57:09 UTC 
cups-1.6.4-10.fc19 has been pushed to the Fedora 19 stable repository.  If problems still persist, please make note of it in this bug report.
Comment 17 Martin Prpič 2014-10-07 08:44:55 UTC 
IssueDescription:

It was discovered that CUPS allowed certain users to create symbolic links in certain directories under /var/cache/cups/. A local user with the 'lp' group privileges could use this flaw to read the contents of arbitrary files on the system or, potentially, escalate their privileges on the system.
Comment 18 errata-xmlrpc 2014-10-14 07:31:42 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 6

Via RHSA-2014:1388 https://rhn.redhat.com/errata/RHSA-2014-1388.html
Comment 19 Tomas Hoger 2015-03-26 21:43:39 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHBA-2015:0386 https://rhn.redhat.com/errata/RHBA-2015-0386.html
Note You need to log in before you can comment on or make changes to this bug.