Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ea4caee1c9b55e3…

MALICIOUS

PDF

81.7 KB Created: 2021-09-06 19:57:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 4f6f7e3033fd1ef6b957ae1b46100923 SHA-1: 67bdd66bcea43367f4fdd8a380d1e40ca0e49edd SHA-256: 8ea4caee1c9b55e357220aa8becaceb88cc926f4db78ccaaaa2e24a57e8f9622
176 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a callback-phone (TOAD) lure. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/780994f35e4aeea2b1971df2877ca17e/pobilubulidiranululuziwi.pdf In PDF document text
    • http://tfforming.ru/d/files/48655769596.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/53b479b810a6eab467e4797043865471/jefawifudifoxonorepunox.pdfIn PDF document text
    • https://protechlighting.com/wp-content/plugins/super-forms/uploads/php/files/6495b0cb0e4a5a846b63694795d54254/68986662226.pdfIn PDF document text
    • https://buildingexpertsdirectory.com/ckfinder/userfiles/files/14169440965.pdfIn PDF document text
    • http://pogservice.ru/userfiles/file/madikuwovuwivibagava.pdfIn PDF document text
    • https://elbag.net/wp-content/plugins/super-forms/uploads/php/files/a79b33b347d6781731eacac6e6fde1b4/jesut.pdfIn PDF document text
    • https://internationalmedia.com/userfiles/file/gumafe.pdfIn PDF document text
    • http://uro-medical.pl/zdjecia/fotki/file/65394876656.pdfIn PDF document text
    • http://krukewittfarms.com/userfiles/file/rivezopanodizilusu.pdfIn PDF document text
    • http://seksdagen.nl/userfiles/file/65581265302.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/eaab0ccaade1d04228d04c9eb27eea45/25281170530.pdfIn PDF document text
    • http://akinmedikal.com/uploads/file/11227011626.pdfIn PDF document text
    • https://cncostruzioni.com/userfiles/file/18984152208.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/f2sdvckn1ecqpmrfmradegjvs6/suzepalokafinomulaza.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/6fb8df21f2560822f7e05080789becf8/lakafazabevuvololasi.pdfIn PDF document text
    • http://ceramkgres.ru/userfiles/file/mikogab.pdfIn PDF document text
    • http://jessie.vn/images/ckeditor/files/35482330349.pdfIn PDF document text
    • http://engineersclasses4competition.com/files/others/80170204644.pdfIn PDF document text
    • https://ktmcollege.org/public_html/userfiles/file/39809033742.pdfIn PDF document text
    • http://clinivetmadonnadirosa.eu/userfiles/files/89845576217.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/160b43a758a6cc---66879992875.pdfIn PDF document text
    • http://shqinze.net/admin/upimg/file///85106175858.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/wikipuludogezuvuwevurili.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/buzav.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082021d3f976---zizonajekolazuditejuwet.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=toefl+independent+writing+template+pdfPDF 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_off0000db3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB3C 17688 bytes
SHA-256: 24c3e2db14ad0157c0b781efa11238aa71474f29ed210c56add75b82e9298609
font_01_sfnt_off000108c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108C8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000120df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120DF 10720 bytes
SHA-256: 1405353ca8416daef95a218fec29c603156ff79def8db4759d2cba01b5cfea81