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

Static analysis result for SHA-256 802adde9cf7128f1…

MALICIOUS

Office (OLE) / .XLSX

369.5 KB
MD5: 74027c02e183634474751315b55c279b SHA-1: d9fc823d7ccd3fde3eb79b46efb403973251e57c SHA-256: 802adde9cf7128f18f09c819b3d4db5357425db1c2b9185b286fb69cf9ae5365
180 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1566 Phishing T1059 Command and Scripting Interpreter

The sample is an encrypted Office XLSX file. Heuristics indicate it uses a default password for encryption and contains an Equation Editor OLE object, a common exploit carrier. The presence of an embedded OLE object within an encrypted OOXML document strongly suggests it's designed to exploit vulnerabilities, likely related to the Equation Editor, to execute malicious code. The file is flagged as an exploit carrier.

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.