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

Static analysis result for SHA-256 2da8f94d09f6c75d…

MALICIOUS

Office (OLE) / .XLSX

1.18 MB
MD5: 29bf3e3b8745a35d7cd8700eca469f94 SHA-1: c5e73d98d363703cda0c68c6fd49a946bad88755 SHA-256: 2da8f94d09f6c75da911b6c68e8bcf382579d96fd1a794463152c48ecf1b67de
100 Risk Score

Malware Insights

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

The sample is an encrypted OOXML file that contains OLE objects, with a high-confidence alert for the Equation Editor OLE object. This strongly suggests it's an exploit carrier designed to leverage CVE-2017-11882. The default encryption further supports its role as a malicious document. No specific family is identifiable from the provided heuristics.

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.