Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 59f1f955f073e2a3…

MALICIOUS

Office (OOXML)

14.7 KB Created: 1996-10-14 23:33:28 UTC Authoring application: Microsoft Excel 15.0300 First seen: 2020-07-24
MD5: d31859fb69340e3d8aee9d8bc98dfed5 SHA-1: 6b31e11e8c43a222bd07cd79273d9013b2137001 SHA-256: 59f1f955f073e2a326d914a15fff168d9c304795270b26bdfb5e1d68d1f96742
120 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The document contains an embedded OLE object, specifically an Equation Editor object, which is flagged as anomalous and indicative of CVE-2018-0798 exploitation. The document body includes a clear 'ENABLE EDITING' prompt, a common lure to bypass macro security. The presence of the OLE object and the lure strongly suggest the document is designed to exploit this vulnerability for initial execution.

Heuristics 4

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Embedded OLE object xl/embeddings/oleObject1.bin contains the Equation Editor CLSID, the legacy component exploited by CVE-2017-11882, CVE-2018-0802, and CVE-2018-0798.
  • CVE-2018-0798 — anomalous Equation Editor native stream high CVE likely CVE_2018_0798_EQUATION_NATIVE_ANOMALY
    Embedded Equation Editor OLE data contains anomalous native stream bytes consistent with a CVE-2018-0798-style Equation Editor exploit. This is treated as likely CVE evidence because the Equation object is malformed and payload-like, but it does not match the exact public matrix-overflow byte signature.
  • Embedded OLE object medium OOXML_OLE_OBJECT
    Document contains an embedded OLE object
  • Macro/content-enable lure medium SE_ENABLE_LURE
    Document instructs the user to enable macros or editing — a common technique used by malware droppers to bypass Office macro security settings

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
ooxml_oleobject_00.bin ooxml-ole-object OOXML embedded OLE part: xl/embeddings/oleObject1.bin 4096 bytes
SHA-256: bb3e745246dcb6df43d93d58381e57e0b1de4765d49778be5cc179ec2c86afaf
ooxml_oleobject_00_ole10native_00.bin ole-package OOXML xl/embeddings/oleObject1.bin Ole10Native stream: oLe10NatIVe 1737 bytes
SHA-256: f537b14a51a83e603d6aa99916e5d60158a2a07fa28affca37691bc358bcd23b