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

Static analysis result for SHA-256 7a446539630540f2…

MALICIOUS

Office (OLE) / .XLSX

646.5 KB
MD5: 5eede2db7597c1e0be62bb3c754ad843 SHA-1: 9c1620f18e58abfbebcf62909f130d1d1d52f4e4 SHA-256: 7a446539630540f2dcdc8c896070e0288d7223503b49917aedb5628a04587205
120 Risk Score

Malware Insights

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

The document is password-encrypted and contains OLE objects, with specific heuristics indicating the use of the Equation Editor vulnerability. This suggests the file is designed to exploit a known vulnerability in Microsoft Office to execute arbitrary code. The presence of embedded OLE objects points towards 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.