Malicious HTML / .PDF — malware analysis report

Static analysis result for SHA-256 5095c6478dbb7f16…

MALICIOUS

HTML / .PDF

151.0 KB
MD5: 7c623d88ed8e325395929d74c98cbb34 SHA-1: 3b73275f5b0419c8f6a601fdacd54c09468d15d2 SHA-256: 5095c6478dbb7f167c637511536ddc9bdc60828cc7c323041c68a2918eb351e8
200 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Service Execution: Visual Basic T1059.007 Service Execution: JavaScript T1105 Ingress Tool Transfer T1204.002 Malicious Link: Malicious File

The HTML file contains VBScript that heavily obfuscates string building to hide its true intent. This script instantiates COM objects like WScript.Shell and uses ShellExecute, indicating it is designed to download and execute a second-stage payload. The presence of a long base64-like payload further supports this delivery mechanism.

Heuristics 6

  • Reference to ShellExecute API high SC_STR_SHELLEXEC
    Reference to ShellExecute API
  • HTML contains VBScript high HTML_VBSCRIPT
    Standalone HTML contains VBScript. Local HTML/VBScript documents are a legacy Windows execution surface commonly used in malicious attachments and browser-exploit chains.
  • HTML script instantiates ActiveX/COM objects high HTML_ACTIVEX_OBJECT
    HTML script calls CreateObject/ActiveXObject, allowing it to reach Windows COM objects such as WScript.Shell, XMLHTTP, or ADODB.Stream.
  • HTML script builds objects and performs synchronous execution high HTML_SCRIPTED_COM_EXECUTION
    HTML script dynamically creates objects and calls execution/open methods in a pattern consistent with staged script malware.
  • HTML script carries a long base64-like payload medium HTML_LONG_BASE64_SCRIPT_PAYLOAD
    HTML script contains a long base64-like blob. This is a common payload-staging technique in HTML smuggling and obfuscated script droppers.
  • HTML script uses heavy string-building obfuscation medium HTML_OBFUSCATED_STRING_BUILDER
    HTML script repeatedly builds short string fragments into variables, a common way to hide object names, URLs, and commands from static scanners.