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

Static analysis result for SHA-256 ae2859599884d445…

MALICIOUS

Office (OLE) / .XLSX

2.25 MB
MD5: f151bca79adbc935da641df0cf4abdda SHA-1: dc9fbb7b77233d68d1f283c89a45346464a74c46 SHA-256: ae2859599884d4455b26bf5ddc941e06d48bfb5642f8bf7159d3945f021729ff
100 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious File

The file is an encrypted OOXML document identified as an exploit carrier. It contains an embedded Equation Editor OLE object, a known vector for delivering malicious payloads. The encryption with a default password further suggests malicious intent. The presence of the Equation Editor exploit points towards an attempt to leverage vulnerabilities for initial compromise.

Heuristics 3

  • 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.
  • 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 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.