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

Static analysis result for SHA-256 2707efc5447f2c6f…

MALICIOUS

Office (OLE) / .XLSX

1.28 MB
MD5: 9a1c3bc1e2f7de44167ed53f036c4d69 SHA-1: 718bfb02fdc4e07d3992043637f613b495178fd6 SHA-256: 2707efc5447f2c6f976c9b8022e3c48f51acfc271e18c2db626c965604d49386
140 Risk Score

Malware Insights

MITRE ATT&CK
T1559.001 Component Object Model Hijacking

The sample is an encrypted OOXML file that contains embedded OLE objects, specifically identified as Equation Editor objects. These objects are frequently used to deliver exploits. The high-entropy Ole10Native stream within the Equation Editor object suggests it carries a malicious payload, though the exact nature of the payload could not be determined from static analysis alone.

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.