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

Static analysis result for SHA-256 953cab6c980f9bc3…

MALICIOUS

Office (OLE) / .XLSX

1.25 MB
MD5: eaa1f4efd2a0edbcc41ab0b9e4a99840 SHA-1: ebc1aab04b764dc1c8645d43df6e43d40e3cc37c SHA-256: 953cab6c980f9bc3659f02ed151114b9f9e2e7de186b45ef441c5687d62a142f
100 Risk Score

Malware Insights

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

The sample is an encrypted OOXML file that utilizes a default password, a common technique for obfuscating malicious content. High-severity heuristics indicate the presence of an Equation Editor OLE object, strongly suggesting exploitation of a known vulnerability within that component. This points to a delivery mechanism via a malicious attachment, likely intended to exploit the Equation Editor to execute further stages.

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.