Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff4b15bc93f998b8…

MALICIOUS

PDF

83.5 KB Created: 2021-07-02 12:29:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: d322a4d68092282038c5d983b8d5af43 SHA-1: df6549a74616bfc92157d1fbfcc0cc328f02153e SHA-256: ff4b15bc93f998b81e6e39a925c5e1a2c824ab053d9af85b559925f556e110ec
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous external links, many hosted on compromised CMS platforms, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple PDF-specific heuristics related to URI and link farms supports this conclusion.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d9af79e2632e45cebdf7fbda96ecf614/24515971430.pdf In PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b9467add7fd---48021266983.pdfIn PDF document text
    • https://joebalogh.ro/imagini_ws/mufixokevawozalekoxis.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/63e47488dc5c98f385643bc98c9d0c80/lobamagaror.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160896e1cddbb6---najutovatesi.pdfIn PDF document text
    • https://mangonebike.com/uploads/file/fubebirukiwarukukugo.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/987503b281338e8f3869ad6d324ef45d/38598083141.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/rfboeajhsjiomie0oi4hv3a6ub/57114148552.pdfIn PDF document text
    • https://service-panev.com/userfiles/xofisakuda.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/na50k9mvqm63gq01fu2rjc8dpm/xajuludusom.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160b5ebe3385c4---34103134696.pdfIn PDF document text
    • http://xedaptap.net/userfiles/file/46243354366.pdfIn PDF document text
    • https://licorne-hotel-restaurant.com/userfiles/file/14410853011.pdfIn PDF document text
    • http://guowangcable.com/d/files/29667476221.pdfIn PDF document text
    • http://cosmic-kino.ru/sadm_files/zefunixu.pdfIn PDF document text
    • https://carstenrath.com/wp-content/plugins/super-forms/uploads/php/files/8pah9b8msqshv11hrviahd5406/kiwuxi.pdfIn PDF document text
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/d36cfa2469cbe6c664021a99d3b09067/nivifidobabidodad.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a7badd1fe55---vadaxotiw.pdfIn PDF document text
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/7qpd4tl9r4okl37p77q8jl2jm8/47977044784.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/160abf6c1d7dc9---74236026883.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/kh8efetl924dv3sebvhomfvd46/jizofisusepugogibuxam.pdfIn PDF document text
    • http://cuatro-pr.org/sites/default/files/file/88585913071.pdfIn PDF document text
    • https://edmaker.site/wp-content/plugins/super-forms/uploads/php/files/b67ccdc01a938027b03462b63fe6848e/60816405691.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=wound+care+for+stage+2+pressure+ulcerPDF 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_off0000e125.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE125 17052 bytes
SHA-256: e2bcb8c3425fe0c0cc000d1133519662941f13df7f1f07db9ef3d526a8b62b4a
font_01_sfnt_off00010d85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D85 10916 bytes
SHA-256: a179a888c229e3fc027c3c4987b88a66ae1379f49814424dc3400a97605753f9
font_02_sfnt_off000126e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126E5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1