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

Static analysis result for SHA-256 3a843efb1f58cbc5…

MALICIOUS

Office (OLE) / .XLSX

197.0 KB
MD5: 825745a31fc275a41849f257818a6e5e SHA-1: 3cbd4431678267fd6660eab67d7c47bc6397e4c6 SHA-256: 3a843efb1f58cbc577e62bbf34451912ac5618c8b79c18ecfa0e0257f927f0cf
100 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The file is an encrypted OOXML document that contains an embedded OLE object, specifically identified as an Equation Editor object. This strongly suggests it's an exploit carrier, likely leveraging a known vulnerability within the Equation Editor. The encryption with a default password further supports its nature as a malicious payload delivery mechanism.

Heuristics 3

  • Equation Editor OLE object high CVE related OLE_EQUATION_EDITOR
    Default-encrypted OOXML 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.
  • Default-encrypted OOXML exploit carrier layout high OOXML_ENCRYPTED_EXPLOIT_CARRIER_SHAPE
    Default-password encrypted OOXML package contains embedded OLE object parts and additional activation/decoy parts. This layout is common in malicious Excel exploit delivery and requires inspecting the decrypted package.
  • Office OOXML encrypted with default VelvetSweatshop password medium OFFICE_DEFAULT_PASSWORD_ENCRYPTED_OOXML
    OLE EncryptedPackage decrypts with Excel's built-in VelvetSweatshop password. Office opens this transparently, and malware uses it to hide OOXML exploit parts from scanners that only inspect the outer OLE container.