Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cb6819037edc224…

MALICIOUS

PDF

77.1 KB Created: 2021-04-07 09:27:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 6eadc354e3677d1fad984455646894e7 SHA-1: 76480087bbdcde7d5ac75c74dab60694666f29f6 SHA-256: 3cb6819037edc224b9423ef96c94abdf13e0ea0bfa5a1cf6af097f623d6390ae
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The document body and embedded URLs indicate a lure for a 'Lecher antenna book pdf free download', which is part of a link farm strategy using multiple disposable domains. While no scripts were explicitly extracted, the PDF structure and the nature of the URLs suggest it may attempt to exploit vulnerabilities or redirect the user to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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 https://www.jsif.org/sites/default/files/webform/54250685962.pdf In PDF document text
    • https://natsihwa.org.au/sites/default/files/webform/17015803.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/49109440539.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/28961662769.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/50635107556.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/7838369457.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/34904816646.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/pidefukil.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=lecher+antenna+book+pdf+free+downloadPDF link annotation
    • https://community.princeton.edu/system/files/webform/tujuxegagisezemesolut.pdfIn PDF document text
    • https://drones.princeton.edu/system/files/webform/94207829768.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/67925993666.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE85 5300 bytes
SHA-256: 64fe74c6d8795377481c05b149bb9eaf80ba32b1f52c42d6732df781d15e1bb5
font_01_sfnt_off0001009e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1009E 11064 bytes
SHA-256: f5a7a2ff118db6005b48c1aa8de81d22e3b223258b8a96a212dc5e12fdeb1cdf