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

Static analysis result for SHA-256 a25d470a134dd5a5…

MALICIOUS

Office (OLE) / .DOC

418.5 KB
MD5: 6e4737d1ae9d34092bb97bf07b036b70 SHA-1: ed6bcf91d914848a8dbdf5daf13c4d9d0dfc7629 SHA-256: a25d470a134dd5a524f2a7c47a15031ba55579e3486ef1903e49e002aabcaef0
220 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1027 Obfuscated Files or Information

The sample exhibits characteristics of a malicious Office document, including a large slack space anomaly and references to WinExec, LoadLibrary, and GetProcAddress APIs, suggesting dynamic code loading. The presence of XOR-encoded strings with a key of 0x03 indicates obfuscation techniques are in use. While no specific exploit is identified, these indicators point towards an attempt to execute arbitrary code, likely to download and run a secondary payload.

Heuristics 5

  • XOR-encoded strings (key 0x03) critical SC_XOR_ENCODED
    Found 8 Windows library/API name(s) XOR-encoded with single-byte key 0x03: 'VirtualAlloc', 'VirtualAlloc', 'VirtualAllocEx', 'VirtualProtect', 'VirtualProtectEx', 'CreateProcessA', 'WriteProcessMemory', 'ReadProcessMemory'
  • Reference to WinExec API high SC_STR_WINEXEC
    Reference to WinExec API
  • Reference to LoadLibrary API high SC_STR_LOADLIBRARY
    Reference to LoadLibrary API
  • Reference to GetProcAddress API high SC_STR_GETPROCADDRESS
    Reference to GetProcAddress API
  • OLE document has large unaccounted-for region high OLE_SLACK_ANOMALY
    OLE file is 428,544 bytes but its declared streams total only 31,351 bytes — 397,193 bytes (93%) 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).