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

Static analysis result for SHA-256 bbceef2cd8724fc8…

MALICIOUS

Office (OLE) / .XLSX

2.47 MB
MD5: e39d819b9e782a42fdf513b228b1a9c4 SHA-1: df578ae1999faac459fe83efe6ad1f997db519a8 SHA-256: bbceef2cd8724fc87db474357e3e08d064ae4211ec9d7bc8367720794c867bd6
100 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution: Malicious Attachment T1559.001 Component Object Model Hijacking

The sample is an encrypted OOXML file that contains embedded OLE objects, with a high-confidence detection for the Equation Editor vulnerability. This suggests the file is designed to exploit CVE-2017-11882. The encryption with a default password further indicates a malicious intent to obscure its contents. No further IOCs were extracted.

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.