Malicious PDF — malware analysis report

Static analysis result for SHA-256 a938c07475da9453…

MALICIOUS

PDF

70.4 KB Created: 2021-06-27 22:50:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 395f1ec3dbb60752517a996d4c2eab08 SHA-1: 2be95d7386678d190eb2dea7780cb17844e6d4ad SHA-256: a938c07475da94537257d02abd97e1cdc13ca3408c3e66e6832c89cb441cec3f
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to potentially malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a non-clustered link farm on disposable hosting, and the PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristic points to links hosted on compromised WordPress upload storage. While no scripts were explicitly extracted, the nature of the link farm suggests an intent to facilitate phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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 http://usaoxin.com/userfiles/2021-5/file/79173781935.pdf
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/20087dc0f17722c94ed8070cc23ce6d3/83447416376.pdf
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/o8tv16os53im0k607g5nr9ik5o/tituwofixajoloresali.pdf
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e8d9ff2250---xokupa.pdf
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/16079eaec6766e---13466835385.pdf
    • http://www.buildingmalawi.com/images/uploaded/documents/16091457736.pdf
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/2urolvdi1t08be0p6r92fvi7ch/19446392290.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079f125b3592---44440242683.pdf
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/647e536b86ff90760a05934176b0a424/muwimuxuxi.pdf
    • https://chmelo.hu/sites/default/files/file/sugukofo.pdf
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/9ae54f379644a947f7a4759d7ff2c634/23768552551.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609594ecc6df6---pisixos.pdf
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607976698f46e---52434140711.pdf
    • https://andana.us/files/files/6837323316.pdf
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090473f62bcc---dizovafuvatuzurajisonoz.pdf
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/eb22f4bb9d5dc26719f03eea4632ea33/91126528966.pdf
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/f0e8c0092359b412af06934956d33b00/86650214564.pdf
    • http://iziusb.com/userfiles//file/26350059143.pdf
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609cf933f3486---43301335700.pdf
    • http://hb1004.com/userData/board/file/73099269165.pdf
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/96fa7894a69889c4372343140c083aa3/4790479974.pdf
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/o8pp3a7t0hp6e9aq4sa48mbc64/4672730899.pdf
    • http://ehomeforeclosure.org/images/file/84362091580.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/clf4frnnb2h0kpm1jj3s50kb0n/bixumipuposidobogi.pdf
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/etunu79ed4o0ln8hisf2eenou4/mabatamupo.pdf
    • https://mmszke.hu/files/file/sojebutamidamodezerolep.pdf
    • https://almoheetmanpower.com/public_html/userfiles/file/87558303662.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=css+fresher+interview+questions
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b794.bin
f37c980f24a1d284ed395be3e36620924f78c7217f0a903201d054d6502c02c1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB794 14568 bytes
font_01_sfnt_off0000dc2c.bin
b8a75aed2b8718e9bfbbd64d3c61a4c33e66a1325ed58fddc7da358e4dd4781e
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC2C 10532 bytes
font_02_sfnt_off0000f436.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF436 16792 bytes