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

Static analysis result for SHA-256 2bb973f392dca900…

MALICIOUS

Office (OOXML) / .XLSX

629.8 KB Created: 2023-08-03 11:34:29 UTC Authoring application: Microsoft Excel 16.0300 First seen: 2023-09-20
MD5: 38c65979391a679a3778ae19b31ef136 SHA-1: ba3233790f0bc26447a7ccfe5ebe3b40b11886d2 SHA-256: 2bb973f392dca90074df33fbdc4cbf893ffe9dd14828e15c6bb2330f43842bef
100 Risk Score

Malware Insights

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

The sample is an Office Open XML file 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 difference, strongly suggesting exploitation of a known vulnerability within Equation Editor. This technique is commonly used to deliver a second-stage malicious payload.

Heuristics 3

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Embedded OLE object xl/embeddings/mha.ZXi 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
4c5479cf7cbc53d7c51aab2c46c3574639b2fea64e01fb4898728271e258650e		 ooxml-ole-object OOXML embedded OLE part: xl/embeddings/mha.ZXi 942080 bytes
ooxml_oleobject_00_ole10native_00.bin
d374eb98194161cd00de58f80c7909f7ae9e3ccb2cb0095c0071b377ae22bda6		 ole-package OOXML xl/embeddings/mha.ZXi Ole10Native stream: oLE10NATive 932345 bytes

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