Malicious PDF — malware analysis report

Static analysis result for SHA-256 b239d2ead6fa6bf3…

MALICIOUS

PDF

83.4 KB Created: 2021-09-17 03:57:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 94dc6f5cfad9b1e6ee7fd0079f911933 SHA-1: a55622a0762738b7370e667fe91d33a89ae7ec52 SHA-256: b239d2ead6fa6bf36f1554c9c551aaa186c89f7bbba7c4342cb4be13142fe562
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing or trojan. It contains numerous embedded URLs that form a link farm, directing users to various external PDF files hosted on potentially disposable domains. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using many distinct hosts with few links per host, a common tactic for evading detection and distributing malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://dcbestwings.com/uploads/files/85407685517.pdf In PDF document text
    • http://hyunshin.net/userfiles/file/54139253363.pdfIn PDF document text
    • http://thietbiotovn.com/Images_upload/files/wuxupeberuxobarojosep.pdfIn PDF document text
    • http://aloisiquadri.it/userfiles/files/3030683225.pdfIn PDF document text
    • http://sunpix.ru/img/lib/file/kukop.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161360a0d91deb---liweko.pdfIn PDF document text
    • https://anpheatingandac.com/nbloom/fckuploads/file/75557081430.pdfIn PDF document text
    • http://drivingtesttips.ie/fckeditor/userfiles/file/55692788261.pdfIn PDF document text
    • http://proficlim.ru/public/userfiles/file/13778497385.pdfIn PDF document text
    • http://thaimassagemodel.com/ckfinder/userfiles/files/25619691036.pdfIn PDF document text
    • http://gtlitalia.com/userfiles/files/6641309473.pdfIn PDF document text
    • http://orthopediedelft.eu/files/24085605236.pdfIn PDF document text
    • https://safetypadlocks.eu/eurostyl/photos/file/kadepanuwuvonuj.pdfIn PDF document text
    • https://www.gullyracing.it/admin/ckfinder/userfiles/files/55181820525.pdfIn PDF document text
    • https://7foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/damaduvekewewim.pdfIn PDF document text
    • https://iwistw.com/upload/files/85127648565.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/61497dbb8e3db2f89f2c0fa4bb620697/40345821714.pdfIn PDF document text
    • http://infinivideo.hu/sites/infinivideo/files/niwadazexotexokib.pdfIn PDF document text
    • http://studiomanzella.com/userfiles/files/64328568470.pdfIn PDF document text
    • http://synagoge-stommeln.de/ckfinder/userfiles/files/95990796130.pdfIn PDF document text
    • http://bukharageorgia.com/sites/default/files/file/zofugewewuranutewigaxaz.pdfIn PDF document text
    • http://bbpcosmetics.com/admin/upFiles/2021-9/file/75940071093.pdfIn PDF document text
    • http://autokolcsonzoszolnok.hu/admin/fck_upload/file/nufonexomu.pdfIn PDF document text
    • https://www.aicsmindia.org/ckfinder/userfiles/files/xadamasime.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=the+secret+lives+of+cheerleaders+streamingPDF 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_off0000e117.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE117 17476 bytes
SHA-256: 92990bb9eedc7673ca43b565e9fc370845eb367469766099a97292d95ea0f0c1
font_01_sfnt_off00010e72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E72 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012689.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12689 10952 bytes
SHA-256: 4451d03e909cd6b822850f7808b8fcdc9f3733d7821878178045f24a263a87be