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

Static analysis result for SHA-256 d1d4de00eec1f8a4…

MALICIOUS

Office (OLE) / .XLSX

228.3 KB
MD5: ed0b2acc25561f6896d7d5761b73cbe3 SHA-1: 6bb20649788e83d50dd7a0b08933b2f7d34bf8d0 SHA-256: d1d4de00eec1f8a48173b341eeb3530ba4f12538d1a112cdcd94ea63a8954d6e
180 Risk Score

Malware Insights

MITRE ATT&CK
T1559.001 Component Object Model Hijacking T1204.002 Malicious File

The sample is a password-encrypted Excel file that contains an embedded OLE object, specifically identified as an Equation Editor object. This combination strongly suggests it's designed to exploit a known vulnerability within Equation Editor to deliver a malicious payload. The encryption and malformed structure further indicate an attempt to evade detection.

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.
  • 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.