Malicious Office (OOXML) / .XLSX — malware analysis report

Static analysis result for SHA-256 4bd917af000ca3cb…

MALICIOUS

Office (OOXML) / .XLSX

1.17 MB Created: 2006-09-16 00:00:00 UTC Authoring application: Microsoft Excel 12.0000
MD5: 9dd7b3e6880d99d62fdc83016de029a1 SHA-1: 5a69458a108158c35313f630b5d258250dadb888 SHA-256: 4bd917af000ca3cb9cb12b49eda140725a4124d3ab311b4e1fd7c0a3af3a1d59
110 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 Malicious Link T1059.003 Windows Command Shell

The file is an Office document containing an embedded OLE object, specifically identified as a Microsoft Equation Editor object. High-severity heuristics indicate that this Equation Editor object carries a payload-like Ole10Native stream with an anomalous header, suggesting it's designed to exploit a vulnerability. The presence of a hidden worksheet further supports the concealment of malicious content. The attack pattern is likely a spearphishing attachment leveraging the Equation Editor vulnerability to execute a payload.

Heuristics 5

  • 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.
  • 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
  • Hidden worksheet (hidden) low OOXML_HIDDEN_SHEET
    Excel workbook contains 1 hidden sheet(s) — hidden sheets are commonly used to conceal macro code, staging data, or intermediate payload construction
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.day.com/dam/1.0
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/tiff/1.0/
    • http://purl.org/dc/elements/1.1/

Extracted artifacts 6

Files carved from inside the sample during analysis.

FilenameKindSourceSize
ooxml_oleobject_00.bin
c77f845fb969677c8a5028585bcd07b1f892130023f873a34ebd96c99862d6dc		 ooxml-ole-object OOXML embedded OLE part: xl/embeddings/oleObject1.bin 950784 bytes
ooxml_oleobject_00_ole10native_00.bin
47f3ca1a2911b78c12b7ece08b0c765493221ba1b6987b326d7f52ea0df0e50d		 ole-package OOXML xl/embeddings/oleObject1.bin Ole10Native stream: OlE10NAtIVe 940917 bytes
ooxml_oleobject_01.bin
090acd44f7b23e5efd21d8f93999abfa1a63cae0219d0117fbc5bf49c35d34d8		 ooxml-ole-object OOXML embedded OLE part: xl/embeddings/oleObject2.bin 10240 bytes
ooxml_oleobject_01_ole10native_00.bin
59fb77315591a55324873430963abffa12244adc4996302250a87d8a758a5796		 ole-package OOXML xl/embeddings/oleObject2.bin Ole10Native stream: Ole10Native 8667 bytes
emf_00.emf
b9960afe44f286accf4d4321eedfd1d97030c046bce240023ff55116ad571a7d		 ooxml-emf OOXML EMF part: xl/media/image9.emf 648132 bytes
emf_01.emf
86497f1d526b69fb8ff6eb2b4fb8cf6378a45c51fe2520ff671e1aa5a4cc631e		 ooxml-emf OOXML EMF part: xl/media/image10.emf 7608 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.