Malicious Office (OLE) — malware analysis report

Static analysis result for SHA-256 413934e841b46e2d…

MALICIOUS

Office (OLE)

660.5 KB Created: 2018-07-26 00:26:51 Authoring application: Microsoft Excel
MD5: 556daf1119d264ba2732fee95b65ea70 SHA-1: c5f9c0af1e044d9751a7b55019bb6e94bf1f8011 SHA-256: 413934e841b46e2dba1902765b5c49d2386736af1492ae274ccb0e50353a388b
296 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic T1204.002 Malicious File

The sample is an Excel document containing obfuscated VBA macros, specifically a Workbook_Open macro designed to execute malicious code. The macro uses CreateObject to instantiate Wscript.Shell and Scripting.FilesystemObject, and then executes a script located at '//klList2.sct' using mshta. This indicates the document is a loader for a second-stage payload.

Heuristics 9

  • Obfuscated auto-exec VBA loader critical OLE_VBA_OBFUSCATED_AUTOEXEC_LOADER
    Auto-exec VBA reconstructs strings with a heavy custom decoder (numeric char-array, repeated hex-string decode, or junk-token Replace removal) and feeds them to a COM-instantiation or execution sink. This obfuscated-loader shape keeps CreateObject/Shell/URL indicators out of the macro source.
  • Reference to Windows Script Host high SC_STR_WSCRIPT
    Reference to Windows Script Host
  • Reference to mshta.exe high SC_STR_MSHTA
    Reference to mshta.exe
  • Workbook_Open macro high OLE_VBA_WBOPEN
    Workbook_Open macro
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
  • VBA p-code auto-exec with execution tokens high OLE_VBA_PCODE_AUTOEXEC_EXEC
    Compiled VBA/cache stream contains an auto-execution token together with shell/download/object-execution tokens. This catches p-code-only or source-extraction-failure macro documents where visible source is unavailable.
  • VBA macros detected medium OLE_VBA_MACROS
    Document contains VBA macro code
  • Environ() call (env variable access) low OLE_VBA_ENVIRON
    Environ() call (env variable access)
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
aa5373c5ae3c1c345ff46e7cf5da2cf1de670c46afb430de289a93fd187abf51
vba-macro oletools.olevba.extract_macros (decoded VBA source) 1210 bytes