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

Static analysis result for SHA-256 7638fde889ef78d1…

MALICIOUS

Office (OOXML) / .XLSX

595.4 KB Created: 2023-07-26 19:45:53 UTC Authoring application: Microsoft Excel 12.0000 First seen: 2023-08-17
MD5: 0528c140962770e32b194e26667663e8 SHA-1: 9305f5411180e151109295b88b56e94ad214e72d SHA-256: 7638fde889ef78d15c8117567c17a934fdd66c7ba98cc4d28be71eb477f1612f
100 Risk Score

Malware Insights

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

The XLSX file contains an embedded OLE object, specifically identified as a Microsoft Equation Editor object. This object exhibits an anomaly where the Ole10Native stream size is significantly smaller than its declared inner size, indicating a potential payload. This technique is commonly used to exploit vulnerabilities in the Equation Editor to execute arbitrary code.

Heuristics 3

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Embedded OLE object xl/embeddings/tsQwlI.iahi 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
89b8169552159aeabab72cda9786d713caee9ec942e227a0fea9e1d681fc7482		 ooxml-ole-object OOXML embedded OLE part: xl/embeddings/tsQwlI.iahi 825344 bytes
ooxml_oleobject_00_ole10native_00.bin
ef739a22e4180b569b9247567c01b75cd2d8643dcf1b1285c654dcd53ed3d731		 ole-package OOXML xl/embeddings/tsQwlI.iahi Ole10Native stream: ole10NaTIvE 816164 bytes

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