Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f18304e5f361dc1…

MALICIOUS

PDF

87.7 KB Created: 2021-08-08 11:13:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 5c5afc4b6d74ff7ea0d7d207e6260f7d SHA-1: 9058d0dfcc24d3f83380944bbead8002e4589c92 SHA-256: 3f18304e5f361dc13e7cb84289b87166c51b3d1262f4518131cc1c8b61aa90ee
236 Risk Score

Malware Insights

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

The PDF file contains a fake CAPTCHA and impersonates Microsoft to trick users into clicking a link for a 'hotmail sign up new account' prompt. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for credential phishing. The embedded URLs point to compromised CMS uploads and link farms, further supporting a phishing attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • Brand-impersonation credential phishing lure high SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: call-to-action link host does not match the impersonated brand: https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=hotmail+sign+up+new+account.
  • 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 http://laboratorioshamalab.com/userfiles/file/14524592053.pdf In PDF document text
    • http://peaceinsrilanka.lk/userfiles/file/tevek.pdfIn PDF document text
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/7d35428a313604af0bdc1645099853ca/bebegiguno.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160d45bcce8b46---xemetokekowejudo.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/1f45b2b348fb9f640f94b9edbf927b8f/71471701263.pdfIn PDF document text
    • http://skncn.com/u/files/motuluvonusi.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084adc6ee383---toduwijovonaxodawivumozu.pdfIn PDF document text
    • http://elijasprojekts.lv/files/file/71435687908.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/90e96d168a39ff21ec41f8e3bd4e1d3f/65535184521.pdfIn PDF document text
    • http://mmprogetti.it/userfiles/files/padivowaxoget.pdfIn PDF document text
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac0b5945922---simutatirizanix.pdfIn PDF document text
    • https://menu2uplus.com/images/file/92304221480.pdfIn PDF document text
    • http://citra.cl/userfiles/file/74012996972.pdfIn PDF document text
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/54e3cad0533e2381c699b4c812241b1c/jaruvewosezejobevekipi.pdfIn PDF document text
    • https://samsungdvmklima.com/upload/ckfinder/files/gixovopirajorolitebabotor.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/wibepadomatazozotisiw.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/f0f516512e068f12813459f46ed37da1/86625284076.pdfIn PDF document text
    • http://i-harmonics.com/upload/files/lidomovup.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16100c04174add---90604578259.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/5m38bprdcr9qefgt3dsdtnilt4/30214210651.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160db6e8bb6143---61619295437.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16093e9dd00b50---moxekanigefibosadivubos.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/160b4052fb0f41---14029181004.pdfIn PDF document text
    • http://imailbox.nl/images/uploadedimages/file/45471534119.pdfIn PDF document text
    • http://merwepizza.com/upload/file/karabo.pdfIn PDF document text
    • http://china-engine.net/ckfinder/userfiles/files/94451330802.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160d91d9e4c3ee---43388278086.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=hotmail+sign+up+new+accountPDF 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_off0000f2ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2CA 10792 bytes
SHA-256: 884a52ba985c155fd8288ab92c7dd1c36c579920b20a814305ca17daff7b648c
font_01_sfnt_off00010bad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BAD 17080 bytes
SHA-256: d8b79d7a4d3df18a06e01940b32cb13fb30ba060cc737561be5dfc84a8aeaa29
font_02_sfnt_off00013806.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13806 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1