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

Static analysis result for SHA-256 5c45fcddd9ea94d5…

MALICIOUS

Office (OOXML) / .XLSX

609.1 KB Created: 2023-09-27 08:05:40 UTC Authoring application: Microsoft Excel 12.0000 First seen: 2023-10-09
MD5: f61ec95e80d0730d3b0f0eb4366efd9d SHA-1: 417e8c439bc18c5cd685949ed3a8df62ae7e5a71 SHA-256: 5c45fcddd9ea94d55fbc3213f1567d7eeedd87a8a6716d02f92ad1d060ce5257
100 Risk Score

Malware Insights

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

The sample is an Office Open XML spreadsheet containing an embedded OLE object, specifically an Equation Editor. Heuristics indicate that this Equation Editor object carries a payload-like Ole10Native stream with an anomalous size difference, strongly suggesting it's designed to execute malicious code. The presence of this embedded malicious object points towards an attempt to exploit vulnerabilities or deliver a secondary payload upon opening.

Heuristics 3

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Embedded OLE object xl/embeddings/GYrLtdv.KW0 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
edb444750bcba4ee406f47667a3615caaba91a21b48d020f58e31d2e3de032b3		 ooxml-ole-object OOXML embedded OLE part: xl/embeddings/GYrLtdv.KW0 830464 bytes
ooxml_oleobject_00_ole10native_00.bin
78805f105c6991e401498d22d77116ffff94e7208690f27c75d859e99b9a7b59		 ole-package OOXML xl/embeddings/GYrLtdv.KW0 Ole10Native stream: OlE10naTivE 821732 bytes

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