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

Static analysis result for SHA-256 1c76deda6c626aff…

MALICIOUS

Office (OLE) / .XLSX

1.19 MB
MD5: 477fef3a87351fcba8331d3e9b96bbd4 SHA-1: 62b780e64ec3c3c8c2a7c0e258e02cb44293fc1f SHA-256: 1c76deda6c626aff1b2e584a1559e789f16b573b1b0fac7f78c553510b29aa0a
140 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious File T1559.001 Component Object Model Hijacking

The sample is an encrypted OOXML file that contains embedded OLE objects, specifically identified as an Equation Editor exploit carrier. The presence of an Equation Editor OLE object with an anomalous Ole10Native stream strongly suggests it's designed to exploit a known vulnerability in that component. This exploit is likely used to deliver a second-stage payload, although the specific payload and its actions are not detailed in the provided evidence.

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.