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

Static analysis result for SHA-256 723add57f8e5a282…

MALICIOUS

Office (OLE) / .XLSX

1.26 MB
MD5: 73d8612bfebed68769e3d0b1c7948768 SHA-1: 2e834dec54bdd6ec6f3bb93b6d4375865c4cab22 SHA-256: 723add57f8e5a282f96536d54ff4223b84f5e7cd1cb259762628fea45b5c7b2e
160 Risk Score

Malware Insights

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

The file is a password-encrypted Excel spreadsheet containing embedded OLE objects, specifically identified as Microsoft Equation Editor objects. The presence of an 'Ole10Native' stream within the Equation Editor object, coupled with an anomaly in its header and size, strongly indicates it's being used as an exploit carrier. This points to exploitation of a vulnerability within the Equation Editor component to achieve code execution, likely delivered via spearphishing.

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.
  • 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.
  • Equation Editor object carries payload-like Ole10Native stream high OLE_EQUATION_OLE10NATIVE_PAYLOAD_ANOMALY
    Default-encrypted OOXML embedded OLE object declares the Equation Editor CLSID but stores a large high-entropy Ole10Native stream with malformed package sizing. This is exploit-shaped Equation/OLE payload evidence.
  • 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.

Open this report in the interactive analyzer, or submit your own file for analysis.