Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6cb4939ca78c37c…

MALICIOUS

PDF

72.7 KB Created: 2021-09-06 13:30:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a4a718b8a11fe0ea472a7e54cb9e56b7 SHA-1: cd973daf789d5f5dacb08c05b453b37ec005bc97 SHA-256: d6cb4939ca78c37ca820d8c871c154a989fa81c73a8040d2c786e8b2a0f8d3f3
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating it likely contains an exploit. It functions as a link farm, with many URLs pointing to compromised websites or disposable hosting, suggesting an attempt to redirect users to malicious content. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://lecourbe.dk/userfiles/file/nesuwepaloninimonugisavob.pdf In PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/fnd70bhr76vdekl063dm2bv641/banixexojexidominarifeva.pdfIn PDF document text
    • http://doubletroubels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f8826eddc4---bizetinubuxapebiwukexubo.pdfIn PDF document text
    • https://silverstonedevelopments.com/ckfinder/userfiles/files/95517253568.pdfIn PDF document text
    • http://wych123.com/upload/files/wajuxaxosiderawisavas.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/1610467d324c1b---50704278293.pdfIn PDF document text
    • http://perfekttorun.pl/pliki/99245262147.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607b29d60fa43---77771888176.pdfIn PDF document text
    • http://dj-venci.com/uploads/pages/files/gadopozofopuzizonuvanixa.pdfIn PDF document text
    • http://prochem.vn/images/uploads/files/nogewijuxijifubapekakewa.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/f4458725c30e13ed7fb421f9f6695732/nenalenemovolafekoz.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/8uisu27m02jn6fi6r2dvsmeeue/27671536672.pdfIn PDF document text
    • https://preprodpcb.com/userfiles/files/vikexemebuzuzowibisunat.pdfIn PDF document text
    • http://jnafarms.com/clients/864068/File/25773199481.pdfIn PDF document text
    • http://tyextractor.com/d/files/lajaduxisinujenasenigo.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/e1a69586ad485e2bac5da4aaba8ceb7b/fejabolewigin.pdfIn PDF document text
    • http://upoart.com/ckfinder/userfiles/files/laloxubiwopukexogimuga.pdfIn PDF document text
    • http://kasintorn.com/images/upload/files/nemolikuposufenu.pdfIn PDF document text
    • https://alteanetworks.fr/img/file/78877945540.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/fnbi2hhms3ikth6io0cgic17b5/runimirotexi.pdfIn PDF document text
    • http://lex.tj/img/file/47067454731.pdfIn PDF document text
    • https://hijaulumut.com/contents/files/gumabud.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/b9e66b36b7fae052984651596aabcb64/46130748528.pdfIn PDF document text
    • https://dreamscapes.ca/dream_scapes/userfiles/files/85587867493.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=looking+for+lovely+bible+study+pdfPDF link annotation
    • https://mediaget.com/userfiles/files/79489796600.pdfIn PDF document text
    • 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_off0000ba34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA34 10980 bytes
SHA-256: ccdbd4c944ca7dd6fa10a211ac87a62f94b939f06341aaf980aa33ab9635db14
font_01_sfnt_off0000d36c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD36C 16200 bytes
SHA-256: 378de6626d983f2c9aac47dc741167f5574a27ea5804305fee98d57e02b68eac
font_02_sfnt_off0000fcfb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCFB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1