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

Static analysis result for SHA-256 1bdabfc281649344…

MALICIOUS

Office (OLE) / .XLSX

1.34 MB
MD5: 6ce7604bee4507ff4b529aba899a8d23 SHA-1: 6fd7d2697d1e03096f394b7501231cdf94ec8cb6 SHA-256: 1bdabfc2816493441e618186ef5c4a2129591b61dc5075909bd6c0e72995078e
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1566 Phishing

The file is an encrypted Office document that contains embedded OLE objects, specifically identified as an Equation Editor object. This object is known to be used as a carrier for exploits, and the presence of an 'Ole10Native' stream anomaly within it strongly suggests it contains a malicious payload. The encryption and the nature of the embedded object point towards a delivery mechanism for an exploit, likely targeting a vulnerability within the Equation Editor itself.

Heuristics 4

  • 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.
  • Equation Editor object carries payload-like Ole10Native stream high OLE_EQUATION_OLE10NATIVE_PAYLOAD_ANOMALY
    Default-encrypted OOXML embedded OLE object declares the Equation Editor CLSID but stores a large high-entropy Ole10Native stream with malformed package sizing. This is exploit-shaped Equation/OLE payload evidence.
  • 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.