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

Static analysis result for SHA-256 267d17cceb7f1b72…

MALICIOUS

Office (OLE) / .XLSX

405.0 KB
MD5: 3c5088ff2855cafbc74c2b42bad74af2 SHA-1: 49e84188317d8ad975f16ecd6ec9f4ae24057be8 SHA-256: 267d17cceb7f1b7202d48cfd7012221c4930c36711082545a4dff32a088a9031
120 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File

The critical heuristic firing indicates the exploitation of CVE-2017-0199 via an OLE object, which is designed to act as a remote loader. The embedded object is encrypted with a default password, suggesting a common exploit carrier technique. The sample's primary function appears to be downloading and executing a second-stage payload from the provided URL.

Heuristics 3

  • 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.
    URL http://tinyurl.mobi/bw4A
  • 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.