Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdb97382938d5914…

MALICIOUS

PDF

22.3 KB
MD5: 44a7e05dc08214f7e395afef96bff289 SHA-1: 005db8ebfcc297cd8dbb14da9e3e8f40e8aac4aa SHA-256: fdb97382938d59141a99cff0c72147c757a702d6446ba27dae970969cd54efae
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 Command and Scripting Interpreter: PowerShell T1204.002 Malicious File: User Execution: Malicious File

The PDF file contains embedded JavaScript, which is heavily obfuscated using eval(), unescape(), and String.fromCharCode(). The primary function of the script appears to be downloading and executing a second-stage payload. Due to the obfuscation, the exact download URL and execution method cannot be confidently determined, leading to a lower confidence score and an unknown family classification.

Heuristics 8

  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj3332_000.js
41b85b352566cdf5433d1a43e699608832fbd07da1d5ce3e5141aea5b1c53f26
pdf-javascript-stream PDF /JS object 3332 at offset 0x5725 252 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 4 eval/decoder/string-building token(s).