Bug 40364

Summary: sudo: multiple issues (4.1)
Product: UCS Reporter: Arvid Requate <requate>
Component: Security updatesAssignee: Arvid Requate <requate>
Status: CLOSED FIXED QA Contact: Daniel Tröder <troeder>
Severity: normal    
Priority: P5 CC: gohmann, walkenhorst
Version: UCS 4.1Flags: requate: Patch_Available+
Target Milestone: UCS 4.1-1-errata   
Hardware: Other   
OS: Linux   
What kind of report is it?: Security Issue What type of bug is this?: ---
Who will be affected by this bug?: --- How will those affected feel about the bug?: ---
User Pain: Enterprise Customer affected?:
School Customer affected?: ISV affected?:
Waiting Support: Flags outvoted (downgraded) after PO Review:
Ticket number: Bug group (optional): Security
Max CVSS v3 score:
Bug Depends on:    
Bug Blocks: 40365, 40366    

Description Arvid Requate univentionstaff 2016-01-05 11:44:41 CET
CVE-2015-5602: sudoedit in Sudo before 1.8.15 allows local users to gain privileges via a symlink attack on a file whose full path is defined using multiple wildcards in /etc/sudoers, as demonstrated by "/home/*/*/file.txt."
Comment 1 Arvid Requate univentionstaff 2016-01-11 20:11:31 CET
Upstream Debian package version 1.8.5p2-1+nmu3+deb7u1 fixes this issue.
Comment 2 Arvid Requate univentionstaff 2016-02-29 20:15:03 CET
The patches have been extracted from the Debian package update and the package has been rebuilt with them in errata4.1-1.

Advisory: sudo.yaml
Comment 3 Daniel Tröder univentionstaff 2016-03-02 13:15:27 CET
OK: advisory
OK: manual test of exploit:

root@Test35:~# dpkg -l sudo
ii  sudo                        1.8.5p2-1+nmu2.39.


root@Test35:~# visudo
>> test01 ALL=(root) NOPASSWD: sudoedit /home/*/*/test.txt

root@Test35:~# su - test01
test01@Test35:~$ mkdir testdir
test01@Test35:~$ ln -s /etc/shadow testdir/test.txt
test01@Test35:~$ sudoedit /home/test01/testdir/test.txt
[can edit shadow file]
sudoedit: /home/test01/testdir/test.txt unchanged

root@Test35:~# DEBIAN_FRONTEND=noninteractive apt-get install sudo
sudo (1.8.5p2-1+nmu2.42.201602292006) wird eingerichtet ...

test01@Test35:~$ sudoedit /home/test01/testdir/test.txt
sudoedit: /home/test01/testdir/test.txt: editing files in a writable directory is not permitted
Comment 4 Janek Walkenhorst univentionstaff 2016-03-08 17:05:42 CET
<http://errata.software-univention.de/ucs/4.1/125.html>