Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f8cc9759506996d…

MALICIOUS

PDF

85.3 KB Created: 2021-09-07 22:52:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 37839c3545da8781122a61735a9bbafb SHA-1: ba45ea6c646bab2e2006b64203987e1d81cf1c13 SHA-256: 9f8cc9759506996df25a0b0c0d2823ac5036fa325fbb77dcc2c357e412452868
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to websites hosted on compromised CMS platforms or disposable domains, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of malicious document delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://tfh-filter.hu/_user/file/12519350207.pdf In PDF document text
    • http://ehomeforeclosure.org/images/file/samizez.pdfIn PDF document text
    • http://arniestribu.com/campannas/file/31376520423.pdfIn PDF document text
    • https://by-express.com/upfiles/editor/files/614841816.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b5845255361---39713396405.pdfIn PDF document text
    • https://okud-istra.hr/userfiles/file/99824724554.pdfIn PDF document text
    • http://www.omt.ntou.edu.tw/ckfinder/userfiles/files/tuzajepufunexokubup.pdfIn PDF document text
    • http://henskeschildersbedrijf.nl/upload/xupob.pdfIn PDF document text
    • http://agendatourvietnam.com/hinhanh/file/warapevokubogawozig.pdfIn PDF document text
    • https://jancsoalapitvany.hu/ckfinder/userfiles/files/sozamewoxexoraduzis.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160d346b4b1693---jalulexonon.pdfIn PDF document text
    • http://vienhung.com/webroot/img/files/63626125832.pdfIn PDF document text
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/3b91e5ed9ffef3a860e9665b800fa4b6/feviwidagefefepelujapameg.pdfIn PDF document text
    • https://egyseg.eu/ckfinder/userfiles/files/39566927093.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f081e52232---21554216185.pdfIn PDF document text
    • https://verlauf-ekb.ru/admin/ckfinder/userfiles/files/91245657254.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a883fbfa7e---92315265442.pdfIn PDF document text
    • http://olneyjune65.com/clients/d/dc/dcef5d22f85ec69f5810ba62c2e8cf46/File/51638135409.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/ee4e077e667f55b5bfcfb9df3d47be1f/nemodunibevinukirukasus.pdfIn PDF document text
    • https://shidoremicrosys.com/media/xolirurupozud.pdfIn PDF document text
    • http://stihoplet.by/upload/editor/files/44980782742.pdfIn PDF document text
    • http://raffaelecavazzoni.com/userfiles/files/fezasofe.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fcf9a7104c---1010316555.pdfIn PDF document text
    • https://fallsplat.se/file/89183348752.pdfIn PDF document text
    • https://jasz-pap.hu/UserFiles/file/gujipexifun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=test+de+niveau+fran%C3%A7ais+4%C3%A8me+pdfPDF 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_off0000db57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB57 11052 bytes
SHA-256: 43ac9bd826e360bcef88353e31a57262a39dfd4871082c7a97b0b6f0f225a8fd
font_01_sfnt_off0000f4de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4DE 21556 bytes
SHA-256: 9f0455d001abbd275adf7b2498a1853e7539dac458913e4c78f8d8e548d61057
font_02_sfnt_off00012c99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C99 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1