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

Static analysis result for SHA-256 ce4fb87abdd92543…

MALICIOUS

Office (OLE) / .XLSX

75.5 KB First seen: 2022-08-25
MD5: 04921cd87e4daa6d49e6e1877328da36 SHA-1: bd48b4338aa1242dcf6d733db25de5d404932455 SHA-256: ce4fb87abdd92543f5d1e52f742a62f19a7ff567ed9e8b6e032912b7bf90d65a
142 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1204.001 Malicious Link: Malicious Link T1059 Command and Scripting Interpreter T1059.001 Command and Scripting Interpreter: PowerShell

The critical heuristic firing for CVE-2017-0199 indicates that this OOXML document is designed to exploit a vulnerability in OLE linking to download a remote document. The embedded URL, http://www.mygreatlearning.com@107.173.192.130/mnc/267.doc, is the primary indicator of this malicious activity. The document is encrypted, which is a common tactic to obscure malicious content.

Heuristics 5

  • OLE2Link / URL Moniker → remote loader — CVE-2017-0199 critical CVE likely CVE_2017_0199
    Document contains an embedded OLE link object whose URL Moniker points to a remote URL. When the host file is opened, Office follows the link, downloads the URL, and processes the response based on its Content-Type (HTA -> mshta.exe, RTF → Word, etc.) — the documented CVE-2017-0199 primitive. The URL extension is not a reliable filter; servers can return different payloads to Office's user agent.
  • 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.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.mygreatlearning.com@107.173.192.130/mnc/267.doc