Malicious PDF — malware analysis report

Static analysis result for SHA-256 a734f13157c706f0…

MALICIOUS

PDF

85.2 KB Created: 2021-09-18 13:28:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6178d24358f093928327c42fc8e5e516 SHA-1: 4056bbe2d85d6fa68f409966287678d04cce45bf SHA-256: a734f13157c706f0df45a893ed3b02a3af80f764280bdaf3b2c6e2f4d39fa8a5
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV, indicating malicious intent. The PDF contains numerous embedded links, many pointing to unknown domains, suggesting a link farm or phishing lure. While no scripts were explicitly extracted, the PDF structure and link farm heuristic suggest it's designed to redirect users to malicious content, potentially for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://fizjolech.pl/userfiles/file/vapixolewakenuvuwodes.pdf In PDF document text
    • http://tischtennis-kiel.de/images/file/fibogi.pdfIn PDF document text
    • http://generaldistco.com/images/file/38707002095.pdfIn PDF document text
    • https://gencshoworganizasyon.com/upload/ckfinder/files/kaguviwewadoletekudigided.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16143b34da3535---77952563135.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/88020876202.pdfIn PDF document text
    • http://elisa5888.com/shopadmin/upload/files/vipogo.pdfIn PDF document text
    • http://pcwenhua.com/uploadimg/file/16305703271271679986.pdfIn PDF document text
    • http://www.hz-kontejnery.cz/ckfinder/userfiles/files/87648323204.pdfIn PDF document text
    • http://gbfrjournal.org/pds/userfiles/files/tabetenasazunorufa.pdfIn PDF document text
    • https://tjp2-hotlink-j3t.com/contents/files/92713529548.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/10775248061.pdfIn PDF document text
    • http://kdsonline.org/userfiles/file/vabuguruguw.pdfIn PDF document text
    • http://abbwingslynnhaven.com/uploads/files/62851075535.pdfIn PDF document text
    • https://aymexco.ro/ckfinder/userfiles/files/negoxul.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210916003513164.pdfIn PDF document text
    • https://gkia.org/kingkong/userfiles/files/rujedezovuxuzazigu.pdfIn PDF document text
    • https://vietrocknet.org/app/webroot/img/files/jukigevi.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16136b42a0fe7e---zopemaroridodusu.pdfIn PDF document text
    • http://tjsijiqing.com/ckfinder/userfiles/files/2021/0906/48e8d023c2417353b81ab14dd9280965.pdfIn PDF document text
    • http://mwcapital.net/ckfinder/userfiles/files/57803382983.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/27mk8er3q49n87ihm7rallan50/ribavamadufiwijid.pdfIn PDF document text
    • https://etevent.itweald.com/uploads/files/61354f764d894.pdfIn PDF document text
    • https://healthtecindia.com/userfiles/file/61323289718.pdfIn PDF document text
    • http://kiko168.com/UploadFile/file/20210902155344847.pdfIn PDF document text
    • http://pzhjintai.com/upload/files/72624741869.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=skyvpn+for+androidPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eab9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAB9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000102d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D0 10396 bytes
SHA-256: 28a3dd804dc4cdc3463ffa80b46002a9ec2dab3e8409b5d7fc0003a491e8bfbd
font_02_sfnt_off00011a72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A72 17436 bytes
SHA-256: 4bf1d49b6a390a937479af74d8fbe6651e825f221b89eda969d5d56779dc6318