Malicious PDF — malware analysis report

Static analysis result for SHA-256 ba148fcf47010aff…

MALICIOUS

PDF

3.8 KB
MD5: bbb68f4f1e7d919c55d039b7ae815578 SHA-1: 4390e0d205e36209359ab638dd0773b8625e4982 SHA-256: ba148fcf47010aff814adcebb3b8206f96dcd7abfca2733d4d2f3c60e6e4961b
142 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/Shell T1204.002 Malicious File

The critical ClamAV detection and high ML classifier score strongly indicate malicious intent. The presence of PDF JavaScript actions, embedded JS streams, and the use of ASCIIHexDecode and ASCII85Decode filters are common indicators of PDF exploits. The ML classifier output of 0.999984 further supports this. The embedded JavaScript is likely responsible for exploiting a vulnerability and downloading a secondary payload, as suggested by the heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • ClamAV: Pdf.Exploit.Agent-36178 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36178
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • ASCII85Decode filter (with exploit indicators) low PDF_FILTER_85
    ASCII85 encoding filter present alongside exploit delivery indicators — uncommon outside of obfuscation