Office (OOXML) / .XLSX malware analysis — malicious · 8c5874b636263ec1

MALICIOUS

Office (OOXML) / .XLSX

1.42 MB Created: 2023-10-19 00:25:29 UTC Authoring application: Microsoft Excel 12.0000 First seen: 2023-10-19

MD5: a80d1cba8d863a26268fac6ab0e176c6 SHA-1: 14ff382cb9d726e77174151022e4b87180803488 SHA-256: 8c5874b636263ec19195e02fa5bbbb2255e89398fb32a82e0300ce9fbe55adb4

142 Risk Score

Malware Insights

MITRE ATT&CK

T1566.002 Spearphishing Attachment T1204.002 Malicious File

The file is an Excel spreadsheet containing an embedded OLE object, specifically a Microsoft Equation Editor object. Heuristics indicate this object is anomalous and likely carries a malicious payload, exploiting CVE-2018-0798. The embedded artifact's high entropy and unusual structure suggest it's designed to execute arbitrary code upon interaction.

Heuristics 5

Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR

Embedded OLE object xl/embeddings/Lp.hFEWR contains the Equation Editor CLSID, the legacy component exploited by CVE-2017-11882, CVE-2018-0802, and CVE-2018-0798.
CVE-2018-0798 — anomalous Equation Editor native stream high CVE likely CVE_2018_0798_EQUATION_NATIVE_ANOMALY

Embedded Equation Editor OLE data contains anomalous native stream bytes consistent with a CVE-2018-0798-style Equation Editor exploit. This is treated as likely CVE evidence because the Equation object is malformed and payload-like, but it does not match the exact public matrix-overflow byte signature.
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
Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE

One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 2

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`ooxml_oleobject_00.bin` `9f3c8bd8dce8257b94003b9e666c1faf82bc01e102f997c892effe02b0ac9ab3`	ooxml-ole-object	OOXML embedded OLE part: xl/embeddings/Lp.hFEWR	1773056 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact entropy is 7.98, consistent with packed or encrypted content.
`ooxml_oleobject_00_ole10native_00.bin` `0ca38cea86be8e455c00346c1be699793fad5939d56010bf2bd180cc69b5962c`	ole-package	OOXML xl/embeddings/Lp.hFEWR Ole10Native stream: olE10naTIVE	1756505 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact entropy is 7.99, consistent with packed or encrypted content.

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