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

Static analysis result for SHA-256 b5d1ef4152c9088d…

MALICIOUS

Office (OOXML) / .XLSX

666.0 KB Created: 2023-07-26 19:45:53 UTC Authoring application: Microsoft Excel 12.0000 First seen: 2023-08-24
MD5: e1237824ac6f527e02855c885ed8063e SHA-1: c520514333231023a8259d8b591b7d0f93db7e01 SHA-256: b5d1ef4152c9088d095850635406a49d6e90c51f45f9b228545bb9d76f633a2f
100 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The file contains an embedded OLE object, specifically identified as an Equation Editor object. High-severity heuristics indicate that this Equation Editor object carries a payload-like Ole10Native stream with an anomalous size, strongly suggesting it's used to exploit a vulnerability. This is a common delivery mechanism for malware, often initiated via spearphishing attachments.

Heuristics 3

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Embedded OLE object xl/embeddings/Z4Ef.z6 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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
ooxml_oleobject_00.bin
7f33b2b2e9d194352ea351b8fd0b532e46fc22b4c4242faa280ceb7bc547a120		 ooxml-ole-object OOXML embedded OLE part: xl/embeddings/Z4Ef.z6 963072 bytes
ooxml_oleobject_00_ole10native_00.bin
029a1e5d32bfbf6fd29ca7fd73f89ef4112febc2081175702f3be1947f570232		 ole-package OOXML xl/embeddings/Z4Ef.z6 Ole10Native stream: Ole10Native 953120 bytes

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