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

Static analysis result for SHA-256 4fd9f4f89554e953…

MALICIOUS

Office (OLE) / .XLS

2.80 MB Created: 2020-09-16 17:35:23 First seen: 2023-09-11
MD5: badae80404f07b411be1970919dbd258 SHA-1: 9115040d3a3d2b6d7c08b4b458ed7f02f1e91642 SHA-256: 4fd9f4f89554e9539a3727e82c11beb21f39e7eff1699107a366017cbed1bfa9
442 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1059.001 PowerShell T1204.002 Malicious File T1566.001 Spearphishing Attachment T1105 Ingress Tool Transfer

The sample is a macro-enabled Excel file containing a Workbook_Open macro that is obfuscated and uses WScript.Shell to execute commands. This indicates an attempt to download and run a secondary payload, likely from the embedded URL http://www.frez.co.uk. The VBA code also shows signs of attempting to manipulate worksheet visibility and data fields, suggesting a lure or data exfiltration purpose.

Heuristics 11

  • Shell() call in VBA critical OLE_VBA_SHELL
    Shell() call in VBA
  • WScript.Shell usage critical OLE_VBA_WSCRIPT
    WScript.Shell usage
  • 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
  • Workbook_Open macro high OLE_VBA_WBOPEN
    Workbook_Open macro
  • CreateObject call high OLE_VBA_CREATEOBJ
    CreateObject call
  • GetObject call high OLE_VBA_GETOBJ
    GetObject 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.
  • Suspicious extracted artifact high EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • VBA macros detected medium OLE_VBA_MACROS
    Document contains VBA macro code
  • 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://www.frez.co.uk

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
f08febc53ba35bb97e35470d6f3d747d888391d473fb96fb1000d82c09bff6bb
vba-macro oletools.olevba.extract_macros (decoded VBA source) 2221791 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).