Malicious PDF — malware analysis report

Static analysis result for SHA-256 df8617f6dda65ee4…

MALICIOUS

PDF

100.9 KB Created: 2021-09-08 21:17:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 8fbdd222f43b8ecee731f5f50b29bc82 SHA-1: 2025e2e5b3b900b8c409115eea9afafdcbd79376 SHA-256: df8617f6dda65ee431e2e7aa64d25f11487dcc8cfd6ecabaa5d92f83a7a7b41a
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to domains associated with link farms or compromised content management systems. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or SEO abuse. The presence of multiple links on potentially compromised or disposable hosting suggests an attempt to distribute malicious content or manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9877

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://bronia.org/userfiles/file/13096804883.pdf In PDF document text
    • http://kukdae.com/files/fckeditor/file/bexuzobiwimanej.pdfIn PDF document text
    • https://isleo.com/i_photos/file/34711050533.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/xiwaxuzidoletinadi.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161321229eb3ad---12623082867.pdfIn PDF document text
    • http://tieulongcopro.com/luutru/files/veligodajuligojubebazi.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/16135dda8f0b37---69117000782.pdfIn PDF document text
    • http://buzmakov-ua.ru/admin/ckfinder/userfiles/files/nogosaripa.pdfIn PDF document text
    • http://www.centrosanmarco.eu/img/news/files/39610879139.pdfIn PDF document text
    • https://oreopay58.com/ckfinder/userfiles/files/34637238835.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/980259007adeb459eb364365dc7c91dc/jowigujerapevutitimuluwe.pdfIn PDF document text
    • http://niengrangchuyensau.com/upload/contentFile/file/2900439614.pdfIn PDF document text
    • https://balbok.net/admin/ckfinder/userfiles/files/wuwuxafiled.pdfIn PDF document text
    • https://fishuntpesca.it/file/31207684516.pdfIn PDF document text
    • http://aias.pnu.ac.th/ckfinder/userfiles/files/nijogu.pdfIn PDF document text
    • http://www.vnv.nu/admin/library/ckfinder/userfiles/files/42063427488.pdfIn PDF document text
    • http://glavis.biz/userfiles/file/voxabujolinikixodut.pdfIn PDF document text
    • http://kortennis.co.kr/B/ck/ckfinder/userfiles/files/26935915483.pdfIn PDF document text
    • http://centromedicoveterinarioadda.com/userfiles/files/firoxoraga.pdfIn PDF document text
    • http://pharmabiosolutions.com/filespath/files/20210904004944.pdfIn PDF document text
    • http://inarchengineering.it/userfiles/files/58069656373.pdfIn PDF document text
    • https://braveathlete.net/geektic/files/tojidopajinobiwopuf.pdfIn PDF document text
    • http://vvk-wiedermann.at/userfiles/file/betuju.pdfIn PDF document text
    • http://rencontres-icare.org/userfiles/file/nonuzawunudesowifog.pdfIn PDF document text
    • http://acunambalaj.com/adenoto/upload/files/3020548838.pdfIn PDF document text
    • http://cyklo-sport-servis.cz/UserFiles/File/40297592519.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=grands+arr%C3%AAts+de+droit+international+priv%C3%A9+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_off00011e21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E21 20788 bytes
SHA-256: 48300a146f8852c5b3f830c6cb62d37a4f0629ae5f3414efda27906de3b0e1a3
font_01_sfnt_off0001522b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1522B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016a42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16A42 10912 bytes
SHA-256: 7e5bf73ec64325e55cc6a37cb1471adde52501116b5b5f9c8b0f61f5534a295b