PDF malware analysis — malicious · e089c643031673f9

MALICIOUS

PDF

25.5 KB Created: 2011-72-51 03:25:00 Authoring application: String.fromCharCode

MD5: 9b49ca20611e8d487b2f651c60a27759 SHA-1: ff092441166f80f992048426dac7e4740b6372ff SHA-256: e089c643031673f922d52a58be5e0410b9010b3c44512f34ea000ea5eca79289

94 Risk Score

Malware Insights

MITRE ATT&CK

T1059.001 PowerShell T1204.002 Malicious File

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including 'PDF_JAVASCRIPT', 'PDF_JS', and 'PDF_METADATA_EVAL_STAGER'. The 'String.fromCharCode' function is used, suggesting obfuscation of JavaScript code within the PDF metadata. The ML classifier also strongly indicates maliciousness. The primary function of the embedded script appears to be executing arbitrary code, likely to download and run a second-stage payload, which is a common technique for initial access.

Machine Learning

Nyx PDF Classifier malicious score 1.0000

Heuristics 4

PDF metadata JavaScript eval stager high PDF_METADATA_EVAL_STAGER

PDF JavaScript reads document metadata fields such as title, subject, or producer, decodes character data with parseInt/String.fromCharCode style helpers, and evals the recovered stage. This is a high-signal exploit-kit staging pattern.
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.

Extracted artifacts 1

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`javascript_obj0001_000.js` `c01eb8d34f911ad4bdc16028c220e189e10dd2dd6f5a6ccbf4416aaa427d90c5`	pdf-javascript-stream	PDF /JS object 1 at offset 0x6325	528 bytes

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