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

Static analysis result for SHA-256 99800df852b01aa6…

MALICIOUS

Office (OOXML) / .XLSX

644.3 KB Created: 2021-10-12 16:50:29 UTC Authoring application: Microsoft Excel 14.0300
MD5: e9f4b286e2b22149360715181f85737e SHA-1: ddbb64b85c2a9b4f14dc1c8433304084c6c84621 SHA-256: 99800df852b01aa636d83b05b5c7f18ec22d3ada11dac31552120799fe77c120
100 Risk Score

Malware Insights

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

The sample is an Excel document containing an embedded OLE object, specifically identified as a Microsoft Equation Editor object. Heuristics indicate that this Equation Editor object carries a payload-like Ole10Native stream with an anomalous size, strongly suggesting exploitation of a vulnerability within the Equation Editor component. This is a common delivery mechanism for malicious payloads.

Heuristics 3

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Embedded OLE object xl/embeddings/yz.Pe9 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
33ef62b5574e0efeb8d7076a06743a83d00df69b3cac33242561b2bafa96c589		 ooxml-ole-object OOXML embedded OLE part: xl/embeddings/yz.Pe9 889344 bytes
ooxml_oleobject_00_ole10native_00.bin
c111d5590b93f3206c563229de2ccaff430524197f2b8382b65bcf95d8044dcb		 ole-package OOXML xl/embeddings/yz.Pe9 Ole10Native stream: olE10NaTIve 879902 bytes

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