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

Static analysis result for SHA-256 83969f9c5a9a6425…

MALICIOUS

Office (OLE) / .XLSX

173.0 KB First seen: 2022-10-10
MD5: 7633437a3c7830d0037ed999d63cccd7 SHA-1: e64aae400008cbf4623b6d1077d33c2a566593ef SHA-256: 83969f9c5a9a64255149bc7cabb0c11bf09ea4afaf662ce0483a4b0725ee375c
142 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution T1059.001 PowerShell

The sample is a password-encrypted Office document that leverages the CVE-2017-0199 vulnerability. This vulnerability allows it to act as a remote loader, fetching and executing a secondary document from the specified URL. The embedded URL is the primary indicator of compromise, suggesting a downloader or exploit delivery mechanism.

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)).
  • 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://doc_dosc@23.254.119.208/uAAuUASDbjasduhuasduyuASHUDHUSADHUASDU/3........................................1.doc