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

Static analysis result for SHA-256 e47c9d823b2d914b…

MALICIOUS

Office (OLE) / .XLSX

317.0 KB
MD5: f75bf4648b7b96495982fa920475dfbe SHA-1: d6f031b52aeeed7b18486ab52aebce0a6ac1b860 SHA-256: e47c9d823b2d914b0ec891b6ce77703371687304181762f20d017e8f2ab18ce0
160 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The sample is a password-encrypted Office document that contains an embedded Equation Editor OLE object. Heuristics indicate this object is anomalous and exploits CVE-2018-0798, a vulnerability in Equation Editor. This suggests the document is designed to exploit this vulnerability to execute arbitrary code. No scripts were extracted, and the document body is inaccessible due to encryption.

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.
  • Office document is password-encrypted medium OFFICE_ENCRYPTED_PACKAGE
    OLE container holds MS-OFFCRYPTO encrypted package (Standard Encryption (Office 2007+, AES-128)).
  • 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.