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

Static analysis result for SHA-256 c9562d75961043a1…

MALICIOUS

Office (OLE) / .XLSX

481.4 KB
MD5: f3b656e3b788ea97cc6cb577ac4ca14a SHA-1: 97d2c21c5d2efc3a40c8a15c71daae702dcad076 SHA-256: c9562d75961043a110fd7f2de8ab2a2fd2bd3def89519f484cf1f197277a24c1
140 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The file is an OOXML document that is encrypted with a default password and contains embedded OLE objects, specifically identified as an Equation Editor exploit carrier. The presence of the 'CVE_2018_0798_EQUATION_NATIVE_ANOMALY' heuristic strongly indicates exploitation of CVE-2018-0798 via the Equation Editor. This suggests the file is designed to execute arbitrary code upon opening.

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.
  • CVE-2018-0798 — anomalous Equation Editor native stream high CVE likely CVE_2018_0798_EQUATION_NATIVE_ANOMALY
    Default-encrypted OOXML contains embedded Equation Editor data with anomalous native stream bytes consistent with a CVE-2018-0798-style exploit. This is treated as likely CVE evidence because the Equation object is malformed and payload-like.
  • 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.
  • 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.