Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6583675dd43c5a0…

MALICIOUS

PDF

115.6 KB Created: 2021-10-11 12:04:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 02919542e596aab361b5fb23964d264f SHA-1: 68b87cc80cff3e1ddd7c454623b818b31671be3c SHA-256: f6583675dd43c5a0dc41258466b53f037e4b9631efeb632170744ea4fe5e185b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised CMS upload directories. The document body is heavily obfuscated and does not provide clear textual lures, but the presence of numerous external links suggests a phishing or redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 https://mhreng.com/userfiles/file/87027842963.pdf In PDF document text
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/jovojesasakib.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/f7965769f2df49c6212b7e50dc67f35d/23888555152.pdfIn PDF document text
    • http://progfin.pl/userfiles/file/muwulamadawopukonoji.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134319acc9fd---lilisezusovulaxeriragogo.pdfIn PDF document text
    • https://mchs.kz/userfiles/File/tabogubobipinobavom.pdfIn PDF document text
    • http://oookub.ru/upload/fckeditor/file/rarokuxenojune.pdfIn PDF document text
    • https://propactionvehiclesuk.tv/userfiles/files/2569318219.pdfIn PDF document text
    • http://boletin.alicantehosteleria.com/lib/ckfinder/userfiles/files/8959709386.pdfIn PDF document text
    • http://jsdarvin.com/files/guzigomogalixisakil.pdfIn PDF document text
    • http://kco.su/userfiles/file/21162746348.pdfIn PDF document text
    • https://sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16163f98c0beee---52225807846.pdfIn PDF document text
    • http://corising.info/sa_upload/userfiles/file/20210921030901.pdfIn PDF document text
    • http://kolorubursztynu.kolorubursztynu.pl/web/uploads/files/71377375709.pdfIn PDF document text
    • http://damnoen.com/ckfinder/pho/files/puxigogibupukulidasogit.pdfIn PDF document text
    • https://nurdagihaber.com/resimler/files/54121827651.pdfIn PDF document text
    • https://maychieuvinh.vn/upload/files/9945094182.pdfIn PDF document text
    • http://xn-----elcksuhhemsi4e.xn--p1ai/files/files/foviboperumegepa.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/89947df5bd2e87c16d560af72c83245d/fasomukexafosugutanupep.pdfIn PDF document text
    • https://goldfieldssanddrags.com.au/ckfinder/userfiles/files/64311836804.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/71415404580.pdfIn PDF document text
    • https://dalycity.com/wysiwygfiles/file/42860421793.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/xPAns0MRe5M/uplcv?utm_term=constable+evans+mystery+series+in+orderPDF 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_off00015806.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15806 10760 bytes
SHA-256: d9958e043e4d3c293ea7c0f148a006497c7bb17b98bcc27f6401bb207644668a
font_01_sfnt_off000170d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x170D1 21084 bytes
SHA-256: 3fbed89305234ad0c2dddd414a4f9fc2c3f4e28c06ce9cd2e2b4c95ae9662bd0
font_02_sfnt_off0001a735.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A735 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1