Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e3810d1d48475c6…

MALICIOUS

PDF

87.4 KB Created: 2021-10-20 09:16:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b251c37fda8edda671f7cca903bdadb6 SHA-1: 4bd8a6fb539f85be29171c32be24db00df64a76a SHA-256: 9e3810d1d48475c6c264a1532fe35cde5951696cb937ec03492ef67be2460378
156 Risk Score

Malware Insights

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

The file is a PDF containing a link farm, with many URLs pointing to disposable hosting or compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or SEO poisoning. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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.
  • 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://binarbaidrealestate.com/public_html/userfiles/file/14028118346.pdf In PDF document text
    • http://hoanhaochemical.com/uploads/files/292707541.pdfIn PDF document text
    • http://movietek.vn/hinh-anh/files/witojabig.pdfIn PDF document text
    • http://atthaya.com/file_media/file_image/file/8742939645.pdfIn PDF document text
    • https://hankilfood.com/userfiles/file/20210919010341.pdfIn PDF document text
    • http://erpos.sk/data/files/60680062172.pdfIn PDF document text
    • http://vallovin.it/userfiles/files/tezetodumamefefito.pdfIn PDF document text
    • http://mathrainbow.com/userfiles/file/19190568523.pdfIn PDF document text
    • https://rintrans.com/files/pofigojobasopubozelof.pdfIn PDF document text
    • http://nextlab-semi.com/files/fckeditor/file/70476690751.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/50943894176.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/3070ffa53d82a5ca514a351ddc632420/tamajomelepakegadipuv.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/78kjni3clr1cipbd76hqkkmn28/9642983137.pdfIn PDF document text
    • http://solarexperten.ch/fckeditor/editor/images/file/40802211843.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/1614fb29f02901---25374935575.pdfIn PDF document text
    • http://songhandiban.com/uploadfile/file/2021092523032573499.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615d1fc44785c---bubuxulurivolowusogozozat.pdfIn PDF document text
    • http://hzjksj.com/images/upload/File/15758937587.pdfIn PDF document text
    • http://tatagz.com/uploadfile/files/52459013452.pdfIn PDF document text
    • https://demowz.reikor.com/webimages/files/74852821236.pdfIn PDF document text
    • http://iproperty.ae/userfiles/file/zodojusasimutil.pdfIn PDF document text
    • http://objets.immoweiss.lu/userfiles/files/38229999418.pdfIn PDF document text
    • http://yokohama-model.com/userfiles/files/428307635.pdfIn PDF document text
    • http://1yunnan.com/ckfinder/userfiles/files/23241014940.pdfIn PDF document text
    • https://yourdentist.ro/app/webroot/files/userfiles/files/93451325964.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/EqozwcbAC44/uplcv?utm_term=ley+de+tensiones+de+kirchhoff+ejercicios+resueltos+paso+por+pasoPDF 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_off0000ecc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECC9 11108 bytes
SHA-256: 8c7c79834a0754e12c100296db5164ee15fd3bdbe4ad5b980baf207f9dcee096
font_01_sfnt_off000106a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106A7 18436 bytes
SHA-256: 20b90e8f403de18c3555b59847c65e805e03d0469f7bd826e14891da0d42099c
font_02_sfnt_off00013517.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13517 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1