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

Static analysis result for SHA-256 91f02087f4681833…

MALICIOUS

Office (OLE) / .XLS

416.5 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 1746950a937d2735d7ad8b8633393471 SHA-1: 3745c72e69666f9799f25d298f71ea05844a0226 SHA-256: 91f02087f468183375ca7489c8936bb562e6d76a4cf39d6402aa9ee672e1c478
128 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution T1059.005 PowerShell

The sample is an Excel file that exploits CVE-2017-0199, a known vulnerability for remote code execution. The heuristic firing indicates it uses an OLE2Link object to fetch a remote loader from the URL http://hop.fyi/sWel7. This suggests the file's primary purpose is to act as a downloader for a second-stage malicious payload. No VBA macros were extracted, but the core exploit mechanism is clearly identified.

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.
  • ClamAV: Xls.Downloader.Trojan-aa0b8f388d8573cd-aa0b8f388d8573cd-9950439-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Xls.Downloader.Trojan-aa0b8f388d8573cd-aa0b8f388d8573cd-9950439-0
  • VBA project contains no executable statements low OLE_VBA_MACROS
    Document contains a VBA project, but extracted modules only contain attributes/options/comments and no executable statements.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
7f506327609c082af1cd37dde23bc2c71a000f7d1ef530b6abb66775040a7673
vba-macro oletools.olevba.extract_macros (decoded VBA source) 1206 bytes