PDF malware analysis — malicious · 5ccae3da809acbb3

MALICIOUS

PDF

15.7 KB

MD5: 4d91c7663f4c742f37417209df591d2c SHA-1: 2343efebd36daac668e2f4dd478b3e58704f47e5 SHA-256: 5ccae3da809acbb35884cac1dfe17f158e5622af69cf871da41228481f435775

256 Risk Score

Malware Insights

MITRE ATT&CK

T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains embedded JavaScript that is heavily obfuscated and utilizes eval() and String.fromCharCode() functions, indicating an attempt to exploit a vulnerability. The ML classifier and ClamAV detection strongly suggest malicious intent, specifically targeting PDF exploitation. The primary function of the script appears to be downloading and executing a secondary payload, as indicated by the exploit cluster heuristics.

Machine Learning

Nyx PDF Classifier malicious score 1.0000

Heuristics 8

PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER

PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
ClamAV: Pdf.Exploit.Agent-36086 critical CLAMAV_DETECTION

ClamAV detected this file as malware: Pdf.Exploit.Agent-36086
eval() call high PDF_EVAL

eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
Large comment-padded JavaScript eval stager high PDF_JS_LARGE_COMMENT_PADDED_EVAL

PDF JavaScript contains a very large stream padded with long random-looking block comments around String.fromCharCode and eval. This is an exploit-kit obfuscation shape used to bury a decoder and recovered stage inside noise, not normal PDF form automation.
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)
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 2

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`javascript_obj0006_000.js` `cfcff91e4af5302ee43a9db799aaa37338f3667667e8e11fea646e791e84f618`	pdf-javascript-stream	PDF /JS object 6 at offset 0x143	425189 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 42 long base64-like blob(s).
`stream_001_off00003b72.bin` `914f8d3f3a60b8f570fe5b66244f2644d54d96bd309707dcf238e14cde22417a`	decompressed-pdf-stream	PDF FlateDecoded stream at offset 0x3B72	300 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.