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

Static analysis result for SHA-256 62be266773541c8f…

MALICIOUS

Office (OLE) / .XLSX

518.0 KB
MD5: beebe31d717b4d28d4bab26450cf58e6 SHA-1: e4d820d781bebdd278170e115cb14236466e0d1c SHA-256: 62be266773541c8f66e2a9e64b72f17a31b10f01eea429c2c3bb6b04dcfc7846
180 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The sample is a password-encrypted Office document identified by ClamAV as Doc.Dropper.Agent-7860000-0. It contains an Equation Editor OLE object, a common carrier for exploits targeting vulnerabilities like CVE-2017-11882. The encryption and presence of exploit-related objects strongly suggest it's designed to deliver a secondary payload upon opening.

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.
  • ClamAV: Doc.Dropper.Agent-7860000-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Dropper.Agent-7860000-0
  • 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-128)).
  • 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.