Malicious PDF — malware analysis report

Static analysis result for SHA-256 23a42f178af90a1a…

MALICIOUS

PDF

81.5 KB Created: 2021-09-11 17:43:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 54f924d05094931aee96dde8c4ff8ba0 SHA-1: 6ca65573a1e39051ea5b9788f01ee6182baa1b82 SHA-256: 23a42f178af90a1a95851b302893f0fe92c919e20ee20ac5f3f34eb8552dd714
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior, indicating a likely attempt to distribute malicious content or phish users. While no scripts were directly extracted, the PDF structure and URL patterns strongly suggest a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 5

  • 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.
  • 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 http://mebizstekla.ru/userfiles/file/volepojubawugen.pdf In PDF document text
    • http://chafewyuok.handysociality.com/upload/files/xowevamiluvoxix.pdfIn PDF document text
    • http://unitez.net/images/newtech/files/fezutov.pdfIn PDF document text
    • http://www.civilhospitalpalampur.in/img/uploads/files/96029257122.pdfIn PDF document text
    • http://3e3i.com/UserFiles/file///41249753577.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138b1ffd95a5---poralukajaguzofiwoz.pdfIn PDF document text
    • https://luxurybaths.marblobaths.ph/app/webroot/img/files/36607080731.pdfIn PDF document text
    • http://unibeauty.com.br/ckfinder/userfiles/files/74326234879.pdfIn PDF document text
    • https://anzhero-sudzhensk.verlauf-ekb.ru/admin/ckfinder/userfiles/files/kakuvezugozejewixefetofi.pdfIn PDF document text
    • http://abakus-routing.co.uk/ckfinder/userfiles/files/71163678285.pdfIn PDF document text
    • http://dkstores.gr/userfiles/file/buvasig.pdfIn PDF document text
    • https://manhremhoangvan.com/wp-content/uploads/files/kafolujutawarajij.pdfIn PDF document text
    • http://ivelinabozilova.com/userfiles/file/mufedidudizo.pdfIn PDF document text
    • https://www.frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/vofogexiwa.pdfIn PDF document text
    • https://licorne-hotel-restaurant.com/userfiles/file/mafeluki.pdfIn PDF document text
    • https://mayphoviet.com/media/ftp/file/sopuxojawuvar.pdfIn PDF document text
    • http://willajarmar.pl/userfiles/file/gufofatuboxowi.pdfIn PDF document text
    • https://lomasdelaweb.com/userfiles/2008.09/file/95406614789.pdfIn PDF document text
    • https://101doctor.com/uploads/ckfiles/files/613942b3b0358.pdfIn PDF document text
    • http://zatoodesign.com/userfiles/files/52199474834.pdfIn PDF document text
    • https://amigo-shop.105h.net/upload/files/36542370210.pdfIn PDF document text
    • https://www.tvmreza.tv/ckfinder/userfiles/files/zonutokofakem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=automatic+call+recorder+mod+apkPDF 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_off0000dab9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAB9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2CB 17592 bytes
SHA-256: b15210d6d14515fcb88f80767b35203951566d5c2df5e35eb72d0265b5a176bf
font_02_sfnt_off0001200c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1200C 10576 bytes
SHA-256: 1b2104902f65913aa88583732611a442b8f2d2b9261b64e0f2e8326dd522f77c