Malicious PDF — malware analysis report

Static analysis result for SHA-256 626c570bc1e43549…

MALICIOUS

PDF

6.4 KB Created: cQÏ4M‰èW±Ú½ráN Authoring application: tJ–fËùW«Ù£qãL (via tJ–fËù6Á¬­X° CCWá }© w1)
MD5: 160c5a12dfbf96572e675e9aec3897da SHA-1: 21a79b3a308cda83325b2ca69b70182ca6ec78e6 SHA-256: 626c570bc1e43549d716addf6663d11236739693f5c48cabb0bf3e833ab67543
88 Risk Score

Malware Insights

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

This PDF sample was flagged as malicious by an ML classifier. It contains embedded JavaScript that is used to encrypt the PDF content, hiding the payload from static analysis. The presence of JavaScript actions and encrypted content strongly suggests the document is designed to download and execute a secondary malicious payload upon opening.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 4

  • Encrypted PDF carries /OpenAction — payload hidden from static analysis high PDF_ENCRYPTED_WITH_JS
    PDF declares /Encrypt and also references an executable trigger (/OpenAction). 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.
  • 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.
  • PDF paints image(s) but contains no text operators info PDF_IMAGE_ONLY_LURE
    PDF has 2 image XObject(s) and the content stream contains no text-emitting operators (BT/ET, Tj, TJ, ', ") in either raw bytes or decompressed streams — this is the screenshot-as-PDF pattern used to bypass text-based scanners and to deliver instructions purely through rendered pixels. It is informational unless paired with invisible links or risky URI context.