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

Static analysis result for SHA-256 b692130f75fe42d2…

MALICIOUS

Office (OLE) / .XLSX

1.16 MB
MD5: 28f6eafcafb2008f462886005bfcdb0f SHA-1: 00bec349b4a20e938449cedf221a22799b186ad7 SHA-256: b692130f75fe42d2e83c578f772eb6af236185c176db19b115862ebf1aaecc41
140 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1559.001 Component Object Model

The sample is an OOXML file that is encrypted with a default password and contains embedded OLE objects, specifically identified as Microsoft Equation Editor. This strongly suggests it's an exploit carrier designed to leverage vulnerabilities within the Equation Editor component to execute a payload. The presence of an anomalous Ole10Native stream within the Equation Editor object further supports this, indicating a potential payload delivery mechanism.

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.