Malicious PDF — malware analysis report

Static analysis result for SHA-256 efff010a6f00802a…

MALICIOUS

PDF

40.4 KB Created: ˜ƒûÃ!=Fž»/´·H9Å0Óc+ Authoring application: ¦]±iʁ`w΋c„ì|| (via ¦]±zʁjwˋb„à|kî^)
MD5: 3d697d3a44cf550b811bbf575b688558 SHA-1: 40035f2bb1214cb7ca82af1b977c370e2cf554f3 SHA-256: efff010a6f00802a3c29003c579bad8a5e0c857499cbb8c0ec26dc1f97370a5c
64 Risk Score

Malware Insights

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

The PDF file is encrypted and contains embedded JavaScript, which is a common technique to hide malicious content from static analysis. The presence of JavaScript actions and streams, along with the 'PDF_ENCRYPTED_WITH_JS' heuristic, strongly suggests that the script is responsible for delivering the actual malicious payload. The obfuscated document body text does not provide clear user-facing content, further indicating a deceptive purpose. The script's exact function is obscured by its size and potential obfuscation, but it is highly probable that it downloads and executes a second-stage payload.

Heuristics 4

  • 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.
  • Optional Content Group with action trigger low PDF_OPTIONAL_CONTENT
    Optional Content Group (layer) co-occurs with an action trigger — content can be selectively hidden from viewers or scanners while the action still fires on open

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0009_000.js
0cf1443766110d7e5191be1b91296890556aef0145549914b9acd3c5178ef06a
pdf-javascript-stream PDF /JS object 9 at offset 0x3D0 38622 bytes