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

Static analysis result for SHA-256 ece4d2f1e91d7233…

MALICIOUS

Office (OLE) / .XLSX

1.18 MB
MD5: e8e5934ac8c39cedfb38985307ee7b03 SHA-1: 2e861bf7dfb04fa42b2b7b31d85122c72d035ce6 SHA-256: ece4d2f1e91d723320e3c6374fa33aca7d05dc03d9403d91ab8388867d43c46b
140 Risk Score

Malware Insights

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

The file is an encrypted OOXML document, identified as an exploit carrier due to the presence of embedded OLE objects, specifically the Equation Editor. The Equation Editor object contains an anomalous Ole10Native stream, indicating it likely carries a malicious payload. This suggests the document is designed to exploit a vulnerability within the Equation Editor to execute arbitrary code.

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.