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

Static analysis result for SHA-256 2d83afb7fee62a56…

MALICIOUS

Office (OLE) / .XLSX

1.19 MB
MD5: 3635d77962fb554b2de873fc6328b56b SHA-1: 12bebfcde4e9228a24fad31bc9acd7fbec542223 SHA-256: 2d83afb7fee62a561e4c8e68e8f5ab76c656976b6e02525ef9f25e6409a67d70
140 Risk Score

Malware Insights

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

The OOXML document is encrypted with a default password and contains embedded OLE objects, specifically identified as an Equation Editor exploit carrier. This exploit carrier contains an anomalous Ole10Native stream, indicating it is designed to deliver a payload. The presence of the Equation Editor OLE object strongly suggests exploitation of a known vulnerability, likely leading to the execution of a second-stage malicious component.

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.