Bug 693824 (CVE-2011-1496)

Summary: CVE-2011-1496 tmux does not drop group tmux privileges properly
Product: [Other] Security Response Reporter: Vincent Danen <vdanen>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED CURRENTRELEASE QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: jrusnack, rosset.filipe, sven
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-11-01 10:50:03 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: 694563, 694564    
Bug Blocks:    
Attachments:
Description Flags
updated patch from Debian (tmux_1.4-6) none

Description Vincent Danen 2011-04-05 16:31:33 UTC 
Created attachment 490029 [details]
updated patch from Debian (tmux_1.4-6)

A Debian bug report [1] noted that tmux did not drop group privileges properly.  On Debian this is a bit of a security risk as tmux seems to be sgid utmp, but on Fedora it is sgid tmux.  In the interest of correcting the behaviour, I'm filing this bug but not as a security bug.  This also would affect tmux in EPEL.

To reproduce:

% SHELL="/bin/dash" tmux -S my_socket
$ id
uid=1001(vdanen) gid=1001(vdanen) egid=482(tmux) groups=1001(vdanen) context=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023


Debian has corrected it with an updated patch (attached).

[1] http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=620304
Comment 1 Vincent Danen 2011-04-07 16:19:01 UTC 
This has been assigned the CVE name CVE-2011-1496, so we have to treat it as a security flaw now.
Comment 2 Vincent Danen 2011-04-07 16:23:01 UTC 
Created tmux tracking bugs for this issue

Affects: fedora-all [bug 694563]
Affects: epel-all [bug 694564]