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

Static analysis result for SHA-256 396998029db75eb9…

MALICIOUS

Office (OLE) / .XLSX

1.20 MB
MD5: 10dc432c53406910beb6308d841fe29a SHA-1: b6c54bcde7c4a793712b83a5e56ceeaa82ed9eca SHA-256: 396998029db75eb9c37abba6494e38161cccacf162583ac42369547698244515
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1566 Phishing T1204.002 Malicious File

The sample is an encrypted OOXML file that contains an Equation Editor OLE object. This object is known to be used to deliver malicious payloads by exploiting vulnerabilities within the Equation Editor. The specific heuristics indicate an anomaly in the Ole10Native stream, suggesting it carries a payload. No document body or scripts were extracted, limiting further analysis of the specific lure or payload.

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.