Malicious PDF — malware analysis report

Static analysis result for SHA-256 3159df1d98a561e3…

MALICIOUS

PDF

90.7 KB Created: 2021-09-05 21:03:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 3ceb193841e386b018b8797e0d670437 SHA-1: d053d18ecf2fd70ac63094032ae36f9e6f96d20f SHA-256: 3159df1d98a561e3fc51a0f2261da194e57592463bc2fa7357b905989122bf72
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • 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.
  • 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://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/0ccebf415dfe4e647e13b9a1030fdde7/fikorafejiwimum.pdf In PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/e6cca3856282b6b35d4e3a4afe3d8231/nekor.pdfIn PDF document text
    • http://langmypham.com/luutru/files/gekepizino.pdfIn PDF document text
    • http://ntweac.edu.hk/admin/ckfinder/userfiles/files/28932462588.pdfIn PDF document text
    • http://grotech.in/userfiles/file/satiz.pdfIn PDF document text
    • https://www.agro-zavod.ru/app/webroot/js/ckfinder/userfiles/files/maxuxeva.pdfIn PDF document text
    • https://webvitamin.vn/app/webroot/uploads/files/judepa.pdfIn PDF document text
    • http://area100impianti.it/userfiles/files/92813040046.pdfIn PDF document text
    • http://capthepcongtrinh.com/uploads/news/files/lujinuga.pdfIn PDF document text
    • https://lapalettedesarts.fr/gestion/file/kilosolobugupapunosijaxew.pdfIn PDF document text
    • http://laarakkers.com/ckfinder/userfiles/files/kekuninawejevevumibane.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16070517537c25---87493172217.pdfIn PDF document text
    • http://vvk-wiedermann.at/userfiles/file/76911525517.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a203ea4f573---26506168978.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/160b712c549120---33114016196.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c95d8d604f0---vubuziweresebe.pdfIn PDF document text
    • http://thankschicken.com/uploads/files/lijajadisavineru.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b3b30b4dd---palififevutak.pdfIn PDF document text
    • http://sameiroeventos.pt/ficheiros/39668563755.pdfIn PDF document text
    • http://polymer-optix.de/userfiles/file/wowipipumedapogobuveva.pdfIn PDF document text
    • https://wccia-vastu.com/wp-content/plugins/super-forms/uploads/php/files/0ef02ffab20459941c474a8d3e685d63/88873279045.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16080340c28c11---miluvumiwin.pdfIn PDF document text
    • https://garnet-medical.com/userfiles/files/rufibobavopavuzeruvakeri.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b4a2e2d670b---22117563324.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=biodegradable+plastic+advantages+and+disadvantages+pdfPDF 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_off0000fdd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDD3 17556 bytes
SHA-256: acc4b1ae4dfb73dae5ebdc8d0e8e7b349d1c8f834774bcf6cc8649e802da3484
font_01_sfnt_off00012af4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001430b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1430B 11052 bytes
SHA-256: b81518b99e69ed169a905b7ce67ff1768f07383dc655b7ec52e2bd9da3c262d9