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

Static analysis result for SHA-256 ea96d3bfb39964e7…

MALICIOUS

Office (OLE) / .XLSX

1.24 MB
MD5: bc610c62b55edcf3c04507c4d9e01f56 SHA-1: d9760cee2dba67707928d561dac1e3368fbeefce SHA-256: ea96d3bfb39964e7456574dece180d7c22476e97eed8c77f8600c9244d1270f5
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1559.001 Component Object Model Hijacking

The sample is an encrypted OOXML file that leverages embedded OLE objects, specifically targeting the Equation Editor (OLE_EQUATION_EDITOR). The presence of an anomaly in the Ole10Native stream within the Equation Editor object (OLE_EQUATION_OLE10NATIVE_PAYLOAD_ANOMALY) strongly suggests it's designed to carry and execute a malicious payload. The file is encrypted with a default password, a common tactic for obfuscation.

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.