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

Static analysis result for SHA-256 0a341a4da84674d4…

MALICIOUS

Office (OLE) / .XLSX

225.0 KB First seen: 2022-10-10
MD5: e6732b3c7a0ddc3548d75bf91443b8c8 SHA-1: e104148da3ec6441beadb0ae7db895ed4e2d4fbe SHA-256: 0a341a4da84674d4d5b954da5fa199811924fa2f658bdb2d7698a7bfdaca94af
220 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.002 Malicious Link: Malicious File T1559 Component Object Model Hijacking T1559.001 Component Object Model Hijacking: Component Object Model Hijacking T1059 Command and Scripting Interpreter

The sample is an encrypted Office document, identified as an exploit carrier for CVE-2018-0798 via a malformed Equation Editor OLE object. This indicates the document is designed to exploit a vulnerability upon opening, likely leading to the execution of a secondary payload. No document body or scripts were extractable due to encryption and malformation.

Heuristics 6

  • 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.
  • Encrypted Office package with CFB FAT corruption critical OLE_ENCRYPTED_AND_MALFORMED
    Encrypted-package shape co-occurs with FAT-chain corruption — the documented combined evasion form.
  • 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)).
  • 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.