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

Static analysis result for SHA-256 d91044f2361c24c0…

MALICIOUS

Office (OLE) / .XLSX

49.0 KB First seen: 2022-08-29
MD5: a9c67e0c098a2fbe177bd093e23645f8 SHA-1: 54197a13cd45ce4d5bea76204e40deb5857f2f72 SHA-256: d91044f2361c24c046baed3b14674c417fa04bf7f1dfca146e315a8e6ca724ad
142 Risk Score

Malware Insights

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

The critical heuristic firing for CVE-2017-0199 indicates that this OOXML file is an exploit carrier. It uses a URL Moniker to download a remote document from http://username@51.81.161.151/...-----.........------------.--.-----------_-----_-------_--/467.doc. The document is password-encrypted, which is a common technique to evade static analysis and hide 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)).
  • 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://username@51.81.161.151/...-----.........------------.--.-----------_-----_-------_--/467.doc