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

Static analysis result for SHA-256 febdbb2078e5f14e…

MALICIOUS

Office (OLE) / .XLSX

1.03 MB
MD5: ad7c902b259476d340eb66125aa4846c SHA-1: 96b5a7b3dbc729d794d9ff1af2701dfc8a82ee24 SHA-256: febdbb2078e5f14e3f534dac4dcf387097c8168f8e803ff98f642b9a99517865
140 Risk Score

Malware Insights

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

The sample is an encrypted OOXML file identified as an exploit carrier. It contains an Equation Editor OLE object, a common technique for delivering malicious payloads. The presence of an anomalous Ole10Native stream within the Equation Editor object suggests it is designed to execute arbitrary code. No specific family could be identified, and no external IOCs were extracted.

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.