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

Static analysis result for SHA-256 bca11a3b1bfdcbda…

MALICIOUS

Office (OLE) / .XLSX

593.5 KB
MD5: da72eecaa13098a2bd8370719a4e2018 SHA-1: 6719efcc0c6f716dc9f540d58baf789415fae522 SHA-256: bca11a3b1bfdcbda7c5e30caf92516ca1eced5b2af7de7a1082c6eb5f3b8f20f
100 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1559.001 Component Object Model

The sample is an encrypted OOXML file that utilizes default password encryption. High-severity heuristics indicate the presence of an Equation Editor OLE object, a known exploit carrier. This suggests the document is designed to exploit vulnerabilities, likely leading to further malicious activity.

Heuristics 3

  • 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.
  • 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.