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

Static analysis result for SHA-256 514ae8892da0386d…

MALICIOUS

Office (OLE) / .XLSX

1.28 MB
MD5: ce6e63b092cbf8f478c0782ceb9d122e SHA-1: 0e6227575150fad52190973f692ccbfdcdf9f79a SHA-256: 514ae8892da0386daa6f2ce6f4278ebbae597c1165e3c0ec05aa5959fecc180e
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious File T1559.001 Component Object Model

The sample is an encrypted OOXML file that contains an Equation Editor OLE object. This object is known to be used as an exploit carrier, and the anomaly detected in the Ole10Native stream suggests it contains a malicious payload. The default encryption password further indicates a likely exploit scenario.

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.