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

Static analysis result for SHA-256 a430c4c3f55897e1…

MALICIOUS

Office (OLE) / .XLSX

1.36 MB
MD5: 0cf3d9eedba4a3f207da831f7fbb2ea8 SHA-1: a2b876d19cc96df552ac612ade1620d4bccc1b40 SHA-256: a430c4c3f55897e166e55d91ace396814d7cc865dd457bb2f17b76a75d340f33
100 Risk Score

Malware Insights

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

The sample is an encrypted OOXML file identified as an exploit carrier. It contains embedded OLE objects, with a specific high-confidence alert for the Equation Editor (OLE_EQUATION_EDITOR). This indicates the file is likely designed to exploit a known vulnerability in Microsoft Equation Editor to deliver a malicious payload. The encryption with a default password further supports its role as a malicious carrier.

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.