Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 8b8960a855603393…

MALICIOUS

Office (OLE)

62.7 KB Created: 1996-12-17 01:32:42 Authoring application: Microsoft Excel First seen: 2013-02-24
MD5: 4f681733fd9e473c09f967fa87c9faef SHA-1: b768c2ce2da94c94bac66221a19e6d51e0cffe19 SHA-256: 8b8960a855603393190152439c64ac9fd16655b304d472ecb83422900369a266
100 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution

The file is an OLE document with a significant amount of slack space, indicating potential obfuscation or embedded malicious content. Although VBA macros could not be extracted due to an unsupported format, the OLE_SLACK_ANOMALY heuristic suggests the file may contain exploitable content. The lack of extractable macros or document body text limits further analysis, but the file structure itself is suspicious.

Heuristics 2

  • 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=23, isf=2, cbHdrData=4294967295). 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.
  • OLE document has large unaccounted-for region high OLE_SLACK_ANOMALY
    OLE file is 64,166 bytes but its declared streams total only 24,565 bytes — 39,601 bytes (62%) 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).