Title: EdrawSoft Office Viewer Component ActiveX 5.6 (officeviewermme.ocx) BoF PoC
Advisory ID: ZSL-2012-5069
Type: Local/Remote
Impact: System Access, DoS
Risk: (4/5)
Release Date: 31.01.2012

Summary

Edraw Office Viewer Component contains a standard ActiveX control that acts as an ActiveX document container for hosting Office documents (including Microsoft Word, Microsoft Excel, Microsoft PowerPoint, Microsoft Project, and Microsoft Visio documents) in a custom form or Web page. The control is lightweight and flexible, and gives developers new possibilities for using Office in a custom solution.

Description

The ActiveX suffers from a buffer overflow vulnerability when parsing large amount of bytes to the FtpUploadFile member in FtpUploadFile() function, resulting memory corruption overwriting severeal registers including the SEH. An attacker can gain access to the system of the affected node and execute arbitrary code.

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(6c9c.6c70): Access violation - code c0000005 (first chance)
First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
eax=00000041 ebx=00001015 ecx=000002a0 edx=001b2edc esi=0186e518 edi=01870000
eip=220324cc esp=0186c488 ebp=0186c490 iopl=0 nv up ei pl nz na pe nc
cs=001b ss=0023 ds=0023 es=0023 fs=003b gs=0000 efl=00010206
*** ERROR: Symbol file could not be found. Defaulted to export symbols for C:\Program Files\Mindjet\MindManager 10\officeviewermme.ocx -
officeviewermme!DllRegisterServer+0x23bbe:
220324cc 668907 mov word ptr [edi],ax ds:0023:01870000=????
0:004> !exchain
0186fa84: 00410041
Invalid exception stack at 00410041
0:004> d esi
0186e518 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186e528 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186e538 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186e548 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186e558 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186e568 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186e578 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186e588 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0:004> d edx
001b2edc 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
001b2eec 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
001b2efc 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
001b2f0c 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
001b2f1c 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
001b2f2c 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
001b2f3c 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
001b2f4c 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0:004> d esp+3000
0186f488 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186f498 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186f4a8 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186f4b8 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186f4c8 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186f4d8 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186f4e8 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0186f4f8 41 00 41 00 41 00 41 00-41 00 41 00 41 00 41 00 A.A.A.A.A.A.A.A.
0:004> !load msec; !exploitable
Exploitability Classification: EXPLOITABLE
Recommended Bug Title: Exploitable - User Mode Write AV starting at officeviewermme!DllRegisterServer+0x0000000000023bbe (Hash=0x55146322.0x550a2c22)

User mode write access violations that are not near NULL are exploitable.

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Vendor

EdrawSoft - http://www.edrawsoft.com

Affected Version

5.6.5781

Tested On

Microsoft Windows XP Professional SP3 (EN)

Vendor Status

N/A

PoC

officeviewer_bof.txt

Credits

Vulnerability discovered by Gjoko Krstic - <gjoko@zeroscience.mk>

References

[1] http://www.zeroscience.mk/en/vulnerabilities/ZSL-2012-5068.php
[2] http://www.exploit-db.com/exploits/18440
[3] http://packetstormsecurity.org/files/109298/ZSL-2012-5069
[4] http://cxsecurity.com/issue/WLB-2012020005
[5] http://www.securityfocus.com/bid/51780
[6] http://www.vfocus.net/art/20120201/9722.html
[7] http://www.osvdb.org/show/osvdb/82322

Changelog

[31.01.2012] - Initial release
[01.02.2012] - Added reference [3] and [4]
[02.02.2012] - Added reference [5]
[04.02.2012] - Added reference [6]
[30.05.2012] - Added reference [7]

Contact

Zero Science Lab

Web: http://www.zeroscience.mk
e-mail: lab@zeroscience.mk