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

Static analysis result for SHA-256 910b1e687bf0031c…

MALICIOUS

Office (OLE) / .XLSX

228.8 KB
MD5: b9bab7464729bcbd5eecf28e598bfe4d SHA-1: e3cf73ecb601581caf7c1cfa4d52e1db65685d7e SHA-256: 910b1e687bf0031c11e812c4c0802e9ca6381621a082fbc39aa87c0d5cdb5da0
180 Risk Score

Malware Insights

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

The sample is an encrypted Excel file that contains an embedded Equation Editor OLE object. This is a known technique for delivering exploits or malware. The file also exhibits CFB FAT corruption, indicating a malformed structure likely intended to evade analysis or facilitate exploitation. No document body or scripts were extractable due to encryption and corruption.

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.