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

Static analysis result for SHA-256 deb10957ab65b83a…

MALICIOUS

Office (OLE) / .XLSX

462.0 KB
MD5: 9b1a1051b36b759d0366d7f81cabc427 SHA-1: 791c5fb52c7a61f07594ce9940e87db0bf0c513e SHA-256: deb10957ab65b83ad78ec961a59b04c415d011c2ae01c1de208138a0df692cea
140 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The sample is an encrypted Office document containing an embedded Equation Editor OLE object. High-severity heuristics indicate the exploitation of CVE-2018-0798 via this object. The document's encrypted nature and the specific exploit targeted suggest it is designed to execute arbitrary code, likely as a downloader for further malicious activity.

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.