Office (OOXML) malware analysis — malicious · a6391652a766c2cf

MALICIOUS

Office (OOXML)

1.04 MB Created: 2018-05-08 06:37:55 UTC Authoring application: Microsoft Excel 15.0300 First seen: 2020-05-25

MD5: 089184453590066e5dc7ab7d6a540741 SHA-1: 38439ad7592ebbbc6627582e08251d10c6273a2a SHA-256: a6391652a766c2cf834152f7aafed3a982f4c9bc857c614395c7481a5fba0f90

142 Risk Score

Malware Insights

MITRE ATT&CK

T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The sample is an Office document containing an embedded OLE object, specifically identified as an Equation Editor object. Heuristics indicate this object is anomalous and carries a payload-like Ole10Native stream, strongly suggesting exploitation of CVE-2018-0798 for client execution. The document body contains what appears to be financial or project-related data in Thai, which could serve as a lure for spearphishing. No scripts were extracted, but the presence of the OLE object is sufficient evidence of malicious intent.

Heuristics 5

Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR

Embedded OLE object xl/embeddings/oleObject1.bin 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`	ooxml-ole-object	OOXML embedded OLE part: xl/embeddings/oleObject1.bin	1081344 bytes
SHA-256: `762295eb34f67501e9188afaf666b2aad55266d12d60e4c8054d40fc4d928d42`
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact entropy is 7.99, consistent with packed or encrypted content.
`ooxml_oleobject_00_ole10native_00.bin`	ole-package	OOXML xl/embeddings/oleObject1.bin Ole10Native stream: oLE10nATive	1070348 bytes
SHA-256: `44fbdbfb2ec9c4abdc20a82f0af012491e7c403fc204c6fbe71556bc359ca40b`
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.