PDF malware analysis — malicious · b4b9596991d4c171

MALICIOUS

PDF

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

MD5: 565a34fce64d00339b472e58d378054f SHA-1: f936431fe7b5c0e7f7dc7c3798442dee52cca555 SHA-256: b4b9596991d4c17189fd1f6feb98d94256bc295966107dd982fc08629e1c321f

64 Risk Score

Malware Insights

MITRE ATT&CK

T1059.001 PowerShell

The PDF file contains embedded JavaScript, identified by the 'PDF_JAVASCRIPT' and 'PDF_JS' heuristics. The 'PDF_METADATA_EVAL_STAGER' heuristic indicates that this JavaScript is used to decode and execute further code, likely a downloader. The use of 'String.fromCharCode' further supports the obfuscation technique. No specific family is identified, but the overall pattern suggests a malicious document designed to download and execute a secondary payload.

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` `f39e89f5bffae8ffb430fe311b97533c3d064d6c240113f755e21e0c27168ff4`	pdf-javascript-stream	PDF /JS object 1 at offset 0x6267	449 bytes

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