Malicious PDF — malware analysis report

Static analysis result for SHA-256 454de89858aa9e99…

MALICIOUS

PDF

261.5 KB Created: 2010-04-21 00:46:53 +08:00
MD5: e228695fd28b3bdd7d9b2012ea8201a9 SHA-1: 178d17018044952f3d4eabd53677ceaff0dab415 SHA-256: 454de89858aa9e99c35ebb8acc9e9b7b907dd5009d1649bde7acf2207add51bd
158 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1566.002 Spearphishing Attachment

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the presence of embedded JavaScript and RichMedia (Flash), which are commonly used to exploit vulnerabilities. The PDF_IMAGE_ONLY_LURE heuristic suggests a deceptive tactic to mask the malicious content. The embedded JavaScript is likely responsible for downloading and executing a secondary payload, as indicated by the ML_NYX_PDF_MALICIOUS score.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9333

Heuristics 8

  • ClamAV: Pdf.Exploit.Agent-35956 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35956
  • RichMedia (Flash) high PDF_RICHMEDIA
    PDF contains /RichMedia (Adobe Flash) which is a historic exploit vector (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. (matched inside decoded stream)
  • 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. (matched inside decoded stream)
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload (matched inside decoded stream)
  • PDF paints image(s) but contains no text operators info PDF_IMAGE_ONLY_LURE
    PDF has 2 image XObject(s) and the content stream contains no text-emitting operators (BT/ET, Tj, TJ, ', ") in either raw bytes or decompressed streams — this is the screenshot-as-PDF pattern used to bypass text-based scanners and to deliver instructions purely through rendered pixels. It is informational unless paired with invisible links or risky URI context.
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PSEOF. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/xap/1.0/
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/photoshop/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/tiff/1.0/
    • http://ns.adobe.com/exif/1.0/
    • http://ns.adobe.com/pdf/1.3/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objstm_0015_00.bin
0bea2f3f6742827130b057b701b07bdcb51c89b49c3509980c44a0392473f8fb
pdf-objstm-decoded PDF /ObjStm 15 0 obj (inflated) 888 bytes