Malicious PDF — malware analysis report

Static analysis result for SHA-256 d91e50c3293cdcf4…

MALICIOUS

PDF

925.5 KB Created: BFO&;á0²LÇp]M9¹?ÝËJ8˜ÆGmÜw°.ېp’`›’¸^ÐóNÝ©» Authoring application: Rêî®t»ÍÕ¨]àÞÿ?Æ×Ñó¬yÜzYJCD°·ñp™¢szÔ\-|ݮϭHcv (via /å=ùìO]ÄM"@?§ï‰™¹jv2ˆ.ø`­\]5øùg ~gÞl¨¡^pfP)
MD5: b0983c8c174ca401531f019c76daf7bd SHA-1: 3834548531e58e15a70b29293176ffd09a6bedd5 SHA-256: d91e50c3293cdcf493029c5011ca895145266c42bd09da63e380ba814d6d129e
104 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1566.001 Spearphishing Attachment T1027 Obfuscated Files or Information

This PDF was flagged as malicious by an ML classifier with high confidence. It contains embedded JavaScript and is encrypted, indicating an attempt to conceal its payload. The presence of PDF_ENCRYPTED_WITH_JS and PDF_JAVASCRIPT heuristics strongly suggests that the JavaScript is used to decrypt and execute malicious content. The PDF_IMAGE_ONLY_LURE heuristic indicates a common tactic to trick users into enabling content or macros.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9769

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.
  • 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.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • PDF paints image(s) but contains no text operators info PDF_IMAGE_ONLY_LURE
    PDF has 1 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.