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

Static analysis result for SHA-256 0e25c027e3c351f9…

MALICIOUS

Office (OLE) / .XLSX

812.5 KB
MD5: f7f710127a3f46698d9a43be94417188 SHA-1: 7fa8a5dadefa5e4b673ee51c71ea5af2b59b0f3c SHA-256: 0e25c027e3c351f978d044715c1e8f464311790b7b7b126482d7028ba6b04880
120 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The sample is a password-encrypted Excel file that contains an embedded OLE object. Heuristics indicate this object is likely an exploit carrier for Equation Editor, a common vector for initial code execution. The default password encryption suggests a common exploit delivery method. The presence of an embedded document further supports its role as an exploit carrier.

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.
  • Office document is password-encrypted medium OFFICE_ENCRYPTED_PACKAGE
    OLE container holds MS-OFFCRYPTO encrypted package (Standard Encryption (Office 2007+, AES-128)).
  • 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.