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

Static analysis result for SHA-256 c2463e44d3ed0bd9…

MALICIOUS

Office (OLE) / .XLSX

2.19 MB
MD5: a50735d9eb8072b0aafd429014dfca34 SHA-1: e8087dfa401897021a8f751005091c7f3bf1d58f SHA-256: c2463e44d3ed0bd9332287d1cc5fb37ab05b4f324eeed42c3e061681f04d466e
180 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1566 Phishing

The sample is an encrypted Office document that utilizes a default password, a common technique for hiding malicious content. It contains an embedded Equation Editor OLE object, specifically flagged for anomalies indicative of exploit code (CVE-2018-0798). This suggests the document is designed to exploit vulnerabilities, likely through the Equation Editor component, to deliver a payload. No specific family could be identified, and no direct IOCs like URLs or hashes were extracted from the provided evidence.

Heuristics 5

  • 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.
  • CVE-2018-0798 — anomalous Equation Editor native stream high CVE likely CVE_2018_0798_EQUATION_NATIVE_ANOMALY
    Default-encrypted OOXML contains embedded Equation Editor data with anomalous native stream bytes consistent with a CVE-2018-0798-style exploit. This is treated as likely CVE evidence because the Equation object is malformed and payload-like.
  • 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.