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

Static analysis result for SHA-256 515c50a60572c34b…

MALICIOUS

Office (OLE) / .XLSX

1.29 MB
MD5: 6f52b7cacc2da41a4b6945310158fc82 SHA-1: 39e0f4ea68407310b4b6e9d41f27285020bb7a5c SHA-256: 515c50a60572c34bffc777448aecb0a778b777bff071d65e5385eedeefc43830
140 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 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 carrier for exploits. The 'OLE_EQUATION_OLE10NATIVE_PAYLOAD_ANOMALY' heuristic indicates that this object likely carries a malicious payload. The exact nature of the payload and its delivery mechanism cannot be determined without further analysis of the embedded object, but the presence of these indicators strongly suggests a malicious intent.

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.