Malicious PDF — malware analysis report

Static analysis result for SHA-256 0e8b4405cd14e489…

MALICIOUS

PDF

42.3 KB Created: 2008-03-03 17:06:20 +08:00 Authoring application: Advanced PDF Repair: http://www.pdf-repair.com
MD5: f8e272893a8774352dca29fabdff2336 SHA-1: 7c62da19350fdd9c589c9e30039bdecc47bb7556 SHA-256: 0e8b4405cd14e48901d85da40697e20bd49349c798a421de9622bd7c625ea17c
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The PDF sample contains embedded JavaScript with multiple eval() calls, indicating an attempt to obfuscate malicious code. The ML classifier and heuristic firings strongly suggest this is a malicious PDF exploiting a known cluster of vulnerabilities. The embedded JavaScript is likely responsible for downloading and executing a second-stage payload, though the exact URL is not directly visible in the provided evidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • 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.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • 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.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.pdf-repair.com
    • http://www.pdf-repair.com)/Producer(Advanced
    • http://www.pdf-repair.com)/ModDate(D:20100406171120+08
    • http://www.w3.org/1999/xhtml
    • http://www.xfa.org/schema/xfa-data/1.0/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://purl.org/dc/elements/1.1/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0038_000.js
d09b3f8531bbd0b9fb1a15b94dac709f7710e3e969ad94204049ce689fed2ee0
pdf-javascript-stream PDF /JS object 38 at offset 0x151D 18155 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).