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

Static analysis result for SHA-256 3ac3857c7c3f5027…

MALICIOUS

Office (OOXML) / .XLSX

611.6 KB Created: 2023-07-26 19:45:53 UTC Authoring application: Microsoft Excel 12.0000 First seen: 2023-08-24
MD5: c9ce130d047a43c337e31864c466a3bc SHA-1: 3a92cf79cae644447b5a14343d88f98843e505ee SHA-256: 3ac3857c7c3f502799d6faa3e8bb6a949fd030ffe134b22f15b1362ad3cf1114
140 Risk Score

Malware Insights

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

The XLSX file contains an embedded OLE object, specifically identified as a Equation Editor object. High-severity heuristics indicate that this Equation Editor object carries a payload-like Ole10Native stream with an anomalous size, suggesting it's used to exploit a vulnerability. The presence of a NOP sled further supports the exploitation of a buffer overflow vulnerability.

Heuristics 4

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Embedded OLE object xl/embeddings/v2eDfay.wEsbl contains the Equation Editor CLSID, the legacy component exploited by CVE-2017-11882, CVE-2018-0802, and CVE-2018-0798.
  • NOP sled detected high SC_NOP_SLED
    Found 20+ consecutive 0x90 bytes
  • 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
8b6f50368de19d4ac34ac36a138e61397698d8fd7cc08e62a661ae8e33c54603		 ooxml-ole-object OOXML embedded OLE part: xl/embeddings/v2eDfay.wEsbl 861696 bytes
ooxml_oleobject_00_ole10native_00.bin
eb0c88d0f807ebd4775984ddefa2abe7ab8ac28724cc9f52fb8fcbdd8833c44e		 ole-package OOXML xl/embeddings/v2eDfay.wEsbl Ole10Native stream: OlE10nATiVe 852121 bytes

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