Malicious Office (OOXML) — malware analysis report

Static analysis result for SHA-256 62fc7861251573aa…

MALICIOUS

Office (OOXML)

2.64 MB Created: 1996-10-14 23:33:28 UTC Authoring application: Microsoft Excel 15.0300 First seen: 2020-05-25
MD5: 1755c096e67786b487eb7cd228b24e8e SHA-1: 3337981c93f1eb47fece46ae44f8762400656b29 SHA-256: 62fc7861251573aa114f1c897d63081ab8a68e65ead2a5b55dabf66cf96d1e3e
162 Risk Score

Malware Insights

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

The file is an Office document containing an embedded OLE object, specifically an Equation Editor object, which is known to be vulnerable to CVE-2018-0798. The heuristics indicate an anomalous and high-entropy Ole10Native stream within this object, suggesting it carries a malicious payload. The document also contains a lure to enable editing, a common tactic for macro-based malware delivery.

Heuristics 6

  • 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.
  • Equation Editor object carries payload-like Ole10Native stream high OLE_EQUATION_OLE10NATIVE_PAYLOAD_ANOMALY
    Embedded OLE object declares the Equation Editor CLSID but stores a large high-entropy Ole10Native stream with malformed package sizing. This is an exploit-shaped Equation/OLE payload container seen in malicious OOXML samples. It is not assigned to a specific CVE unless the MTEF/Equation Native primitive also matches.
  • 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
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

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 2772480 bytes
SHA-256: 72098467de2ce9d815c791fb8c9457670008e0e11c6b2ac26a65eb954c199df9
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.97, consistent with packed or encrypted content.
ooxml_oleobject_00_ole10native_00.bin ole-package OOXML xl/embeddings/oleObject1.bin Ole10Native stream: ole10NaTiVe 2748341 bytes
SHA-256: 7f0fcb244f1026c58e94369360705ab92d954007d90a4083d7818dfad8cceab4
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.99, consistent with packed or encrypted content.