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

Static analysis result for SHA-256 ab6c4dee1d0c821a…

MALICIOUS

Office (OLE) / .XLSX

177.3 KB
MD5: 4e2121086dc08814a0d98c136bddd1c6 SHA-1: 358232da42d90724788c8bf8a0f5a9d24114938d SHA-256: ab6c4dee1d0c821adf8f05a64d48d1282339dab5b34cff3566c35ca14018f2bd
180 Risk Score

Malware Insights

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

The sample is an encrypted Excel file identified as an exploit carrier. It contains an Equation Editor OLE object, a common vector for exploiting vulnerabilities in older Microsoft Office versions. The file's structure indicates it is designed to deliver a malicious payload via this embedded object.

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.