Malicious PDF — malware analysis report

Static analysis result for SHA-256 9d49389ba9a63eb6…

MALICIOUS

PDF

25.4 KB Created: 2011-72-51 03:25:00 Authoring application: String.fromCharCode
MD5: 7b613814738c74e96da14c85cd2d9380 SHA-1: f4ff853d3e4e99a49404c60eda2c6211f32730f7 SHA-256: 9d49389ba9a63eb6def77816975f5f6d2c10c2054c8391f4a5724c8630c26d75
64 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell

The PDF file contains JavaScript embedded within its metadata, which is a common technique for obfuscating malicious code. The heuristic 'PDF_METADATA_EVAL_STAGER' indicates that this JavaScript is likely used to decode and execute a payload. The use of 'String.fromCharCode' further suggests code obfuscation. While no specific family is identified, the overall pattern points to a downloader or stager.

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.

FilenameKindSourceSize
javascript_obj0001_000.js
cbd0959a2e54e35d0d73601252775d8a40900edac45bb815e696920bf72a6226
pdf-javascript-stream PDF /JS object 1 at offset 0x628F 516 bytes