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

Static analysis result for SHA-256 937049fd1bbea6e4…

MALICIOUS

Office (OLE) / .XLSX

1.00 MB
MD5: e896984ddb7fa0dc78f4ead0c84bf345 SHA-1: 91bb8da305288c47b3ed62fe092395530314b885 SHA-256: 937049fd1bbea6e4c5dffb1276cb7f75e0d18c8b37f520a458c9bde79e016ff3
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious File T1566 Phishing T1204.002 Malicious File: User Execution

The sample is an OOXML file encrypted with a default password, indicating an attempt to hide its malicious contents. High-severity heuristics indicate the presence of an Equation Editor OLE object that carries a payload-like stream, a common technique for exploiting vulnerabilities like CVE-2017-11882. No document body text or scripts were extracted, but the structure strongly suggests a malicious exploit carrier.

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.