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

Static analysis result for SHA-256 dae4a56c510e999c…

MALICIOUS

Office (OLE) / .XLSX

1.07 MB
MD5: 997200828416e51e43dd1cab16ed4e75 SHA-1: 6645e445eef002c5820ddfae294df63142e56074 SHA-256: dae4a56c510e999c93f4995532eed2c857787143d7f8e999a4ca00f777f4e98f
140 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The OOXML document is encrypted with a default password, indicating it's likely an exploit carrier. High-severity heuristics indicate the presence of an Equation Editor OLE object containing a payload-like stream, a common technique for exploiting Equation Editor vulnerabilities. The presence of embedded OLE objects further supports this. No scripts were extracted from this sample.

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.