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

Static analysis result for SHA-256 7b20de1d2525a1ca…

MALICIOUS

Office (OLE) / .XLSX

1.15 MB
MD5: 4e74a70899aa1af8e8232012c343852e SHA-1: 13d5de1d0f50dfc0ee3d6a199173b324ee6e779f SHA-256: 7b20de1d2525a1cad912a61ce5dddeeac439db2a5fcb18ddfbce96082e342a0e
140 Risk Score

Malware Insights

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

The OOXML document is encrypted with a default password and contains an Equation Editor OLE object, which is a known exploit carrier. The presence of an Ole10Native stream within the Equation Editor object suggests it is designed to deliver a secondary payload. This combination of factors points to a malicious document intended to exploit vulnerabilities upon opening.

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.
  • Equation Editor object carries payload-like Ole10Native stream high OLE_EQUATION_OLE10NATIVE_PAYLOAD_ANOMALY
    Default-encrypted OOXML embedded OLE object declares the Equation Editor CLSID but stores a large high-entropy Ole10Native stream with malformed package sizing. This is exploit-shaped Equation/OLE payload evidence.
  • 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.