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

Static analysis result for SHA-256 873b857810477d70…

MALICIOUS

Office (OOXML) / .XLSX

654.2 KB Created: 2023-07-26 19:45:53 UTC Authoring application: Microsoft Excel 12.0000 First seen: 2023-10-11
MD5: 9733b3d902601eb1eb1708470a8cfb7b SHA-1: 48f99da68781b82c318191c01298e8f9ea16a2f2 SHA-256: 873b857810477d70682a70fa8f4e5d839609bba27a20d77d27324c8ff7303e1d
100 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious File

The file is an Excel spreadsheet 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, strongly suggesting it's being used to exploit a vulnerability. This technique is commonly used to deliver second-stage malware.

Heuristics 3

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Embedded OLE object xl/embeddings/UsA.rY 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
95eb7cb55cb9d90e277bb2cb4300f67114a1ae0027b522c5ddd05916f351541a		 ooxml-ole-object OOXML embedded OLE part: xl/embeddings/UsA.rY 897536 bytes
ooxml_oleobject_00_ole10native_00.bin
eab4587e9c41f8e43782f21cdc0175f6137fb82560385d9a39f01a01176d1834		 ole-package OOXML xl/embeddings/UsA.rY Ole10Native stream: OLE10native 887913 bytes

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