Win.Trojan.Melissa-4 — Office (OLE) / .DOC malware analysis

Static analysis result for SHA-256 1a940149b0acbe01…

MALICIOUS

Office (OLE) / .DOC

32.0 KB Created: 1999-04-02 18:37:00 Authoring application: Microsoft Word 8.0 First seen: 2023-06-01
MD5: bc45d5f03ad760afaf36def831d0328e SHA-1: b87a79b7062c5cc776cd69e659776a0332bf4be5 SHA-256: 1a940149b0acbe01d5b765872ca30d359d8ec90ddf8282d479207677c3404d02
300 Risk Score

Malware Insights

Win.Trojan.Melissa-4 · confidence 95%

MITRE ATT&CK
T1059.005 Visual Basic T1505.003 Server Software Component: Email Collection T1071.001 Web Protocols: Web Protocol

The sample is a Microsoft Word document containing VBA macros, specifically an AutoOpen macro, which is a common delivery mechanism for older malware. The script attempts to disable security features and leverage Outlook to email itself to contacts, a hallmark of the Melissa virus family. The ClamAV detection of 'Win.Trojan.Melissa-4' further supports this attribution.

Heuristics 7

  • ClamAV: Win.Trojan.Psycho-3 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Win.Trojan.Psycho-3
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • AutoOpen macro high OLE_VBA_AUTOOPEN
    AutoOpen macro
  • Document_Open macro high OLE_VBA_DOCOPEN
    Document_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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
macros.bas
b272887adbe23144b74256bb8722ccb04bd1ffc7501dfcde4d3fee5c93ce03be
vba-macro oletools.olevba.extract_macros (decoded VBA source) 13135 bytes
Detection
ClamAV: Doc.Trojan.Melissa-4
Obfuscation or payload: unlikely