Bug 1376826

Summary: guest_t can run sudo
Product: Red Hat Enterprise Linux 6 Reporter: Stefan Kremen <skremen>
Component: opensshAssignee: Jakub Jelen <jjelen>
Status: CLOSED NOTABUG QA Contact: Stefan Dordevic <sdordevi>
Severity: high Docs Contact:
Priority: high    
Version: 6.8CC: jjelen, ksrot, lvrabec, mgrepl, mmalik, nmavrogi, plautrba, pvrabec, qe-baseos-security, skremen, szidek
Target Milestone: rc   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: 1357859
: 1378463 (view as bug list) Environment:
Last Closed: 2016-11-02 12:00:55 UTC Type: Bug
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: 1356245, 1357857, 1357859, 1357860    
Bug Blocks: 1378463    

Comment 7 Jakub Jelen 2016-09-29 08:34:33 UTC 
The main concern in this bug is that confined user guest_t have setuid and setgid SELinux capabilities, which can be "misused" by sudo (or other tools?).

Generally, for running sudo, there are needed underlying Linux capabilities, access to other files and finally being in the sudoers file. The consequence of fixing this bug is mostly hardening SELinux policy, based on the original report. I also asked Miroslav to confirm this explanation and add if I missed something.
Comment 8 Lukas Vrabec 2016-09-29 14:10:29 UTC 
Jakub is right. We should fix this in RHEL-6.
Comment 10 Jakub Jelen 2016-11-02 12:00:55 UTC 
Based on our meeting with Lukas yesterday, we decided to fix this bug only in selinux-policy and therefore this is not bug in OpenSSH.

The openssh in RHEL6 is using special selinux user chroot_user_t which has the permissions to chroot, setuid and setgit permissions.
On the other hand the guest_t users do not need the setuid and setgit permissions, therefore they will be removed based on the selinux-policy bug.