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

Static analysis result for SHA-256 80aadcd04ea940c5…

MALICIOUS

Office (OLE) / .XLS

92.5 KB Created: 1996-12-17 01:32:42 Authoring application: Microsoft Excel
MD5: 759c8a47745a8889c9bbe67719b607a0 SHA-1: cdb3016be24ddae0e90ca90938aa1fc2d72ebc16 SHA-256: 80aadcd04ea940c5b0130451b313b5951193e3c6a82bc88735951615469ea60b
220 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The critical heuristic firing for CVE-2009-3129 indicates that this Excel file exploits a known vulnerability to achieve code execution. The presence of an appended payload and suspicious cmd.exe invocation further suggests that the exploit is used to download and execute a secondary stage. The exact nature of the payload is not discernible from the provided evidence.

Heuristics 5

  • CVE-2009-3129 — Excel FEATHEADER record overflow critical CVE exact CVE_2009_3129
    Workbook BIFF stream contains a FEATHEADER (Feature Header) record with anomalous size (record_size=22, isf=4, cbHdrData=4). Legitimate FEATHEADER records are tiny (<100 bytes) and carry cbHdrData values that fit in the record body; the value here is the documented CVE-2009-3129 exploit primitive — cbHdrData drives a memcpy with attacker-controlled size, leading to memory corruption and code execution in Excel 2007/2003.
  • PEB access via FS segment (x86) high SC_PEB_ACCESS
    PEB access via FS segment (x86)
  • Suspicious cmd.exe invocation with execution flag high SC_STR_CMD
    Suspicious cmd.exe invocation with execution flag
  • OLE document has large unaccounted-for region high OLE_SLACK_ANOMALY
    OLE file is 94,669 bytes but its declared streams total only 24,565 bytes — 70,104 bytes (74%) 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).
  • OLE file has appended executable-looking payload bytes high OLE_APPENDED_PAYLOAD
    OLE compound file contains a large high-entropy region beyond the declared major streams and that region includes shellcode, PE, or loader API markers. This is a payload-carrier signal, not a specific CVE attribution by itself.