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

Static analysis result for SHA-256 26f202c4761338c9…

MALICIOUS

Office (OOXML) / .XLSX

743.2 KB Created: 2021-12-06 14:45:17 UTC Authoring application: Microsoft Excel 12.0000 First seen: 2022-03-07
MD5: b379d8475af2fd332e7630636de40637 SHA-1: 9c2b81a1597667b069a83f72e06c2e5d839cec6a SHA-256: 26f202c4761338c95a35330997316822becd62d94451254aa4c98f0555b0b6fd
100 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious File T1559 Component Object Model Hijacking

The sample contains 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. This points to an attack pattern where the user interaction with the document triggers the exploitation of the Equation Editor to download and execute a secondary payload.

Heuristics 3

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Embedded OLE object xl/embeddings/sTK0bZ.t41 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
42889939a51c419589c140038b599fb8b0707012a925aefa39060c4abe7954a8		 ooxml-ole-object OOXML embedded OLE part: xl/embeddings/sTK0bZ.t41 1051648 bytes
ooxml_oleobject_00_ole10native_00.bin
7fb4474a0f8319e84b4c12fa36ea88216b7a50653902f406271b7ffe1ac0dd49		 ole-package OOXML xl/embeddings/sTK0bZ.t41 Ole10Native stream: OLE10nAtive 1040856 bytes

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