Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a7f6a6347c339f8…

MALICIOUS

PDF

92.2 KB Created: 2021-07-01 19:50:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: c12ea2987fff7740d39670bbbe311d3c SHA-1: b7506f138528358f0435d04c86544ac24c0b4264 SHA-256: 7a7f6a6347c339f8cdd78c2c1fa9c05a75f84a109a4c275b1c4a2aa45477f6f7
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. The heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking readable content that would suggest a specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • 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.
  • 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://bajajsports.com/userfiles/file/buzimudokivobuxa.pdf In PDF document text
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/83a77dbd42b334cd8a8eb4d66d8ef78e/lifuk.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608841a022d21---27258352185.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/biegtsojmbnvm3tkg6dhbqm8bj/kitowajurizilewipu.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/5ccc0dad6cd058f2b16d93415baacc57/46350426398.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///pisajigix.pdfIn PDF document text
    • http://dostavkaturov.ru/files/file/xerenuwolezeka.pdfIn PDF document text
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/fm5ce7tropku47a3tlmgckg32f/ralovuzawebapo.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607f21ee8f63f---dawivisomakeluv.pdfIn PDF document text
    • https://altbuket.ru/files/pukoj.pdfIn PDF document text
    • https://mn-lawfirm.com/box/userfiles/file/fukov.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/c90651b3cfb2513e394f2def220ae013/99645383899.pdfIn PDF document text
    • http://sbs-group.co/userfiles/files/xiponoza.pdfIn PDF document text
    • http://allprintusa.com/admin/images/file/98391487249.pdfIn PDF document text
    • https://prokoncept.hu/admin/blogfck/image/file/10693216029.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/63khai8vn2k7rmoorpuqkqsoft/wopapisazasej.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071e6b9682c0---16166683429.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/qqlqirm5aboia7bvfn2iagi3cn/vavasuk.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/d58b22553d75314eee5c5e7a3cb746af/dilebisolisuwubis.pdfIn PDF document text
    • http://wecans.net/_UploadFile/Images/file/34051507930.pdfIn PDF document text
    • http://creaorganization.com/depo/sayfaresim/file/15814949140.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/ec3bc7vng4lj9h82mm87f3tct3/4449009320.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/0f7444b61c56235a953d252cf5fde44a/rafetiwupebutidalumovisog.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/8q8ccn25vai2ehlbpq3dbfu8sc/xorodewidepepadovirotot.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=collinear+points+on+a+planePDF 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_off00010493.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10493 10276 bytes
SHA-256: 99e4941326d3acf859c77fc7ecbeff42eeca2cec64d50db8cceb476368ffa06a
font_01_sfnt_off00011bd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BD2 17856 bytes
SHA-256: 7617725c7ad8e166892e5800204538f0516a744ceb2d43d093bbe4d52fb982c8
font_02_sfnt_off00014b49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14B49 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1