Malicious PDF — malware analysis report

Static analysis result for SHA-256 8aebf9ae3370a054…

MALICIOUS

PDF

800 B
MD5: cd097507ebe6e9080130dcd29b9d1ce8 SHA-1: 91a6abdbda0158ad0b497e381cfd19a33a91a8a7 SHA-256: 8aebf9ae3370a054f7330c84eab5956ec5a8c792a63e4432f3c5c1d867d52817
120 Risk Score

Malware Insights

MITRE ATT&CK
T1059.003 Windows Command Shell T1204.002 Malicious File T1071.001 Web Protocols

The PDF file contains a launch action that executes cmd.exe. This command is designed to echo a VBScript payload to a file named 'm.vbs'. The VBScript is obfuscated using string reversal and concatenation, but analysis indicates it will likely download and execute a second-stage payload from the embedded URL http://79.135.152.194/a/tmp/m.vbs. The embedded script payload heuristic further supports this finding.

Heuristics 4

  • Launch action high PDF_LAUNCH
    PDF contains a /Launch action with an unresolved or extension-less target — treat as potentially dangerous
  • Embedded script payload in PDF stream high PDF_EMBEDDED_SCRIPT_PAYLOAD
    PDF stream bytes contain script execution markers such as ActiveXObject/CreateObject, WScript.Shell, PowerShell, or shell-exec primitives. This is stronger than ordinary PDF JavaScript because it indicates a staged external script payload hidden in stream bytes.
  • /Launch action target: cmd high PDF_LAUNCH_COMMAND
    PDF /Launch action specifies an executable target with parameters '/c echo B="m.vbs":With CreateObject(StrReverse("PTTHLMX.2LMXSM"'.
  • 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://79.135.152.194/a/tmp/m.vbs

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_pdf_script_0000006f.bin
ad55c8e83a5896a04b2012c676820daeab2b84cc539e444c6366e79f55a571c5
pdf-embedded-script PDF decompressed stream script payload at offset 0x6F 63 bytes