Malicious PDF — malware analysis report

Static analysis result for SHA-256 61877a0bf161af2b…

MALICIOUS

PDF

8.0 KB Created: 2008-31-20 53:85:00 Authoring application: Scribus 1.3.3.12 (via Scribus PDF Library 1.3.3.12)
MD5: d44a8d7df3009d24cf19d1499b4fa0f3 SHA-1: e6c582564272763b0cfb7ea70a75794c4ea3073d SHA-256: 61877a0bf161af2b6308bfb6d3137574cfafe0e429ac0e7d6586865cc70c7a97
270 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, including obfuscated code that utilizes eval() calls, strongly indicating an exploit attempt. The JavaScript is designed to download and execute a second-stage payload from one of the embedded URLs. ClamAV detections further confirm the malicious nature of the file, classifying it as Pdf.Exploit.Agent-35587.

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-35587 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35587
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution
  • 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.
  • 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://phpnet.us/byet300x250.php
    • http://ad.foxnetworks.com/st?ad_type=pop&ad_size=0x0&section=204717&banned_pop_types=28&pop_times=5&pop_frequency=86400

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0013_001.js
a391efca2a22f1313078d6034027294f62c5810455ee5ad2a89f75e0123b86c4
pdf-javascript-stream PDF /JS object 13 at offset 0x3D5 5887 bytes
Detection
ClamAV: Pdf.Exploit.Agent-35587
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).