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

Static analysis result for SHA-256 3cb021f727c306bc…

MALICIOUS

Office (OOXML) / .XLSX

740.9 KB Created: 2023-07-26 19:45:53 UTC Authoring application: Microsoft Excel 12.0000 First seen: 2023-09-20
MD5: ff4afba38fca387b209a6058da8583ec SHA-1: 75118d306f18f4574018ad5d24e725ff3bee49b2 SHA-256: 3cb021f727c306bcc8a733554521981f4bfd5e9b3e39d733d601e7a69291d602
100 Risk Score

Malware Insights

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

The file is an Excel document containing an embedded OLE object, specifically identified as a Equation Editor object. Heuristics indicate that this Equation Editor object carries a payload-like Ole10Native stream with an anomalous header and size mismatch, strongly suggesting exploitation of a known Equation Editor vulnerability. The embedded OLE object is likely the initial vector for delivering a second-stage malicious payload.

Heuristics 3

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Embedded OLE object xl/embeddings/7MDMTQn.5m 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
7e916225a0723404835d03161894e050d1aec5c39995b9b16eac0ea1c5a089ec		 ooxml-ole-object OOXML embedded OLE part: xl/embeddings/7MDMTQn.5m 1100800 bytes
ooxml_oleobject_00_ole10native_00.bin
b96db191218e0c259999b8fa9acd27bbd98048f94fa6453a6911a031446223ba		 ole-package OOXML xl/embeddings/7MDMTQn.5m Ole10Native stream: olE10NativE 1089547 bytes

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