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

Static analysis result for SHA-256 7a1ad5e5128c745a…

MALICIOUS

Office (OLE) / .XLSX

310.3 KB
MD5: dd6c250fc2a7c0dc156ecfabd0bc8e60 SHA-1: 0aeb6da6b08dde69b11ae66fed7b0b2e9b466d67 SHA-256: 7a1ad5e5128c745a8b2ac2ea4645bdc08dd8a8c80e9af88a21d3a7c4a96b315b
180 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.002 Malicious File

The sample is an encrypted Office document that contains an Equation Editor OLE object, a known carrier for exploits. The document is also flagged as malformed and encrypted with a default password, indicating an attempt to obscure malicious content. The combination of these factors strongly suggests it's designed to deliver a payload via an Equation Editor vulnerability.

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.