Malicious Office (OLE) / .DOC — malware analysis report

Static analysis result for SHA-256 cb8442d1eb2dd98f…

MALICIOUS

Office (OLE) / .DOC

80.3 KB Created: 2006-08-16 17:20:00 Authoring application: Microsoft Office Word
MD5: de35fe711b72da7f63d0017e8634b812 SHA-1: 6a0fe6c60928152c4be7bfb0081c38798fcf60c5 SHA-256: cb8442d1eb2dd98fe7b96ad5b870d85a00d62f69f4d736d902586ba54810b424
100 Risk Score

Malware Insights

MITRE ATT&CK
T1027 Obfuscated Files or Information

The sample exhibits significant slack space within its OLE structure, a common characteristic of packed or obfuscated malware. The critical heuristic firing confirms the presence of XOR-encoded strings with a key of 0x81, indicating an attempt to conceal malicious code or data. While no specific family is identifiable, the obfuscation strongly suggests a downloader or a stage-one payload designed to evade static analysis.

Heuristics 2

  • XOR-encoded strings (key 0x81) critical SC_XOR_ENCODED
    Found 4 Windows library/API name(s) XOR-encoded with single-byte key 0x81: 'kernel32.dll', 'advapi32.dll', 'shell32.dll', 'ExitProcess'
  • OLE document has large unaccounted-for region high OLE_SLACK_ANOMALY
    OLE file is 82,237 bytes but its declared streams total only 17,055 bytes — 65,182 bytes (79%) live in unallocated sector slack. This is the canonical hiding place for pre-macro-era Office exploit payloads (XOR-encoded shellcode reached via a parser pointer-corruption bug in the document structure).