Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd64feeedb939a17…

MALICIOUS

PDF

17.71 MB
MD5: a035053db1199a80d97da18292ecd5ef SHA-1: 2cb7240382cb6d9fcac377c2e179c0d61d77344e SHA-256: bd64feeedb939a17de651b466e8f34c0bb2f46007193d8f8741b751255fb4179
122 Risk Score

Malware Insights

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

The PDF file exhibits multiple high and medium severity heuristic firings indicating malicious intent, including the presence of encrypted JavaScript and the use of ASCIIHexDecode filters. The ML classifier strongly flags this PDF as malicious. The embedded JavaScript, though obfuscated, is likely used to bypass static analysis and deliver a secondary payload. The file's SHA256 hash is provided as a primary IOC.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

Heuristics 6

  • Encrypted PDF carries /JavaScript — payload hidden from static analysis high PDF_ENCRYPTED_WITH_JS
    PDF declares /Encrypt and also references an executable trigger (/JavaScript). Document encryption hides the JavaScript body and stream contents from static scanners — combined with auto-execution indicators this is a known evasion pattern used to deliver weaponised JavaScript that the analyst cannot inspect without the decryption key.
  • 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.
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • Additional-actions dictionary low PDF_AA
    PDF defines /AA (Additional Actions) that references an executable action (JS/JavaScript/Launch/SubmitForm) — can auto-trigger on document or widget events. Form-field calc/format/validate/keystroke handlers in legitimate interactive forms commonly fire this, so it is reported as a low-weight signal; weaponised auto-execution is flagged by stronger rules (PDF_OPENACTION, encrypted-with-JS, etc.)