Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3263fc4863a3938…

MALICIOUS

PDF

81.3 KB Created: 2021-08-25 23:37:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: d6d185d6f87b684b292552c32925fe88 SHA-1: 430f96ce13e577ac71b30bbf35af7431d56a53d4 SHA-256: f3263fc4863a3938870a815e772fc319438e42fcb9d4e82f6f352e80b0123872
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous links pointing to various domains, many of which are hosted on compromised CMS upload storage, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues to its specific purpose beyond the presence of these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://opuntia.eu/wp-content/plugins/super-forms/uploads/php/files/0d89de9695a6acbd985f4fa845943bb3/60965777075.pdf In PDF document text
    • http://reicar.dk/userfiles/file/begafatajivop.pdfIn PDF document text
    • http://medica-brno.com/files/60758957902.pdfIn PDF document text
    • http://www.contectrade.hu/fckfiles/file/58331969628.pdfIn PDF document text
    • http://historico.uts.edu.co/portal/app/ckfinder/userfiles/files/gekofozomenotox.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16075c3aee8789---6122886720.pdfIn PDF document text
    • http://kasargod.net/uploads/file/daxubaguz.pdfIn PDF document text
    • http://www.badischer-kunstverein.de/ckfinder/userfiles/files/muzixozuwoxasudififexugel.pdfIn PDF document text
    • http://cukorbetegshop.hu/files/fubupagimuwanuxizib.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/j7htnoimer1t01tvtnh23vgk4m/tanexetaxaxarirepu.pdfIn PDF document text
    • http://dirpub.org/editor/ckfinder/userfiles/files/78384359641.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/4771376189.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/s27d40jpcie52qdi1sr8ghssp8/visoteruluroninulakawatu.pdfIn PDF document text
    • https://zoorichi.com/temp/fckeditor/file/50813353114.pdfIn PDF document text
    • https://himalayanwanderer.com/himalayan/userfiles/files/jejito.pdfIn PDF document text
    • http://fitviewer.biz/files/file/sovatutusuzuselenap.pdfIn PDF document text
    • http://shiraz.sk/ckfinder/userfiles/files/rusibomewexajomijer.pdfIn PDF document text
    • http://beautybybelief.com/admin/images/file/regiroz.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aba301a099f---guxezabajojoliba.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1607fda7c94ad7---9183966338.pdfIn PDF document text
    • https://allmassage.net/upload/file/20210607063625.pdfIn PDF document text
    • http://stolizstekla.ru/userfiles/file/76499574605.pdfIn PDF document text
    • http://vhktn.at/images/content/files/nagawujetemexaxi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=come+on+to+my+house+rosemary+clooneyPDF 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_off0000dcfa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCFA 15888 bytes
SHA-256: 9a5137c9673c55bbd1a5e4849f8bb217fc0829a86be752afa0d4c1dc28c25ab9
font_01_sfnt_off000105f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E0B 10648 bytes
SHA-256: 06ec55ca7d16af5621ace32646c1844c072db406000e6c614c9ed283e0a12343