Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5f455092d763795…

MALICIOUS

PDF

796 B
MD5: 5a0efa6420fb051462ac004a04fc6452 SHA-1: fe8a2af3a835c577e92e916682abf5e68708a265 SHA-256: b5f455092d763795edf3db562a2f67562977c7df34ba1550a43368d02e91d62c
120 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1566.002 Spearphishing Attachment

The PDF contains a launch action that executes cmd.exe, which in turn echoes a VBScript payload to a file named 'm.vbs'. This script is designed to download and execute a second-stage payload from the embedded URL http://mjef.info/m5/tmp/m.vbs. The obfuscated string 'PTTHLMX.2LMXSM' is a reversed form of 'Scripting.FileSystemObject', indicating the script's intent to interact with the file system and execute downloaded code.

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://mjef.info/m5/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