Malicious PDF — malware analysis report

Static analysis result for SHA-256 1436f7743a8e0b7f…

MALICIOUS

PDF

89.5 KB Created: 2021-07-14 07:56:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5101ada8530d539d03d8583e748a673b SHA-1: a9bde46b909fe5c5f06da87d43d3773b7a3be13e SHA-256: 1436f7743a8e0b7ff782b200a843564f6ce38ca33090ec7597d24ac213b76673
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites acting as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160711b08d06b6---72233489263.pdf In PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/160965559c6915---83906635553.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c34126d8338---rujipufuji.pdfIn PDF document text
    • http://ipost.mn/ckfinder/userfiles/files/wakedinuzisojefezet.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16087d4be8306c---kolugumumelumora.pdfIn PDF document text
    • https://www.mnspineandsport.com/wp-content/plugins/super-forms/uploads/php/files/40081f0dbdefe1a4000274a22942cdc7/nifopasuzidape.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/jaragitur.pdfIn PDF document text
    • https://useoneconvo.com/wp-content/plugins/super-forms/uploads/php/files/e50e37231575b86f45cb295c24c406ea/fugavegoxigavataw.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160983b6c065de---89584609696.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160df9e37dd9b8---ligerejamo.pdfIn PDF document text
    • https://watfordfairtrade.org/app/webroot/img/files/8495414399.pdfIn PDF document text
    • https://www.elitelawnsolutions.co.uk/wp-content/plugins/super-forms/uploads/php/files/4s7kk14528nmq2sg3pu0b77a53/6004632802.pdfIn PDF document text
    • http://broadviewlibrary.org/uploaded_bvlib/file/rusakud.pdfIn PDF document text
    • http://i-dron.cz/data/file/48686431770.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///nepajulifawuwe.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070e74f83f88---87033889453.pdfIn PDF document text
    • https://corumosmanlimakina.com/js/ckfinder/userfiles/files/88236000602.pdfIn PDF document text
    • http://jandebruijn.com/uploadimages/files/57379511634.pdfIn PDF document text
    • http://eltonltd.ru/sites/default/files/uploads/puxasunuba.pdfIn PDF document text
    • https://liantoong.com/archive/upload/files/17999622838.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072e8cc24463---taposi.pdfIn PDF document text
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cff9f88c9f---10638601654.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=oxygen+cylinder+portable+for+homePDF link annotation
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/f728d29a889bc7872ac063660e195702/ridutituridutivokaxopixef.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_off0000fa31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA31 17436 bytes
SHA-256: edc73a29d02ab267013976d95708595d5ef8147a7eb57c9840d627b4b8ebf29d
font_01_sfnt_off000126fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013f13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F13 11280 bytes
SHA-256: aef7bd75de9df7a6242ef4b49b06c5449ea2d58739cfeddbfdfb59eb6f5159a6