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

Static analysis result for SHA-256 36a96f3eaba0f196…

MALICIOUS

Office (OLE) / .XLSX

2.41 MB
MD5: d92414b9067c16cb85448a1d57495033 SHA-1: 289708f65413544d5162c5c6814efe24da10b38b SHA-256: 36a96f3eaba0f196e2a300d1200154b29a82165b0fe7e308ed67076d8464a88c
100 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The sample is an encrypted OOXML file identified as an exploit carrier. It contains an embedded Equation Editor OLE object, a common technique for delivering exploits. The encryption with a default password further suggests malicious intent. While no specific family is identified, the presence of the Equation Editor points to a likely exploit delivery mechanism.

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.