Malicious PDF — malware analysis report

Static analysis result for SHA-256 dfda2799f43234d7…

MALICIOUS

PDF

93.2 KB Created: 2021-08-25 17:07:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 277cab44a6b272eed567051da6c8e3c1 SHA-1: 25aaf1164ee3a195591a17c8f87885bc638188b1 SHA-256: dfda2799f43234d708b602403258bee451b6a91884ce7ce7e070dc0d32ed103e
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. Multiple URLs point to compromised CMS uploads and disposable hosting, suggesting a phishing or SEO spam campaign. No scripts were extracted, but the overall structure and URL distribution indicate a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://kulturazebrak.cz/userfiles/59328920102.pdf In PDF document text
    • http://0-50.ru/userfiles/file/jovofuwidudej.pdfIn PDF document text
    • https://reitinguok.lt/userfiles/file/87512156121.pdfIn PDF document text
    • https://kuepancong.com/contents//files/xekin.pdfIn PDF document text
    • https://mahae.hu/files/files/49606613716.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/4b1ae5432fc4977cd139ba676a6151a3/33384248890.pdfIn PDF document text
    • https://akproauto.net/nbloom/fckuploads/file/kilalitafokipobigije.pdfIn PDF document text
    • http://matstravel.ru/userfiles/file/94296581585.pdfIn PDF document text
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/03d5f641045a64b5e1cf4386c7e06fc7/xulefibapakur.pdfIn PDF document text
    • https://nodka.eu/ckeditor/ckfinder/userfiles/files/60022664070.pdfIn PDF document text
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089fec2c55da---vasilupudejiporuzevozos.pdfIn PDF document text
    • http://mirai-kankyo.com/userfiles/files/21004682469.pdfIn PDF document text
    • http://trendybiz.in/usersfiles/file/51251226184.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/93988556856.pdfIn PDF document text
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/44347e7b582d2b106aeef447c003315c/munexodibepurewaxopobodex.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080da5deb27b---62337013508.pdfIn PDF document text
    • http://fence-alarm.com/userfiles/files/nanajamivawo.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a847bfc8197---nowozujaka.pdfIn PDF document text
    • http://maynenkhipuma.vn/quangbasanpham/app/webroot/upload/image/files/62200721874.pdfIn PDF document text
    • http://hongshengfish.com/uploadfiles/20210608/2106081021323542244mme6uijcg59.pdfIn PDF document text
    • https://aynispirit.nl/userfiles/file/zarabirekotafumuxanogu.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/94l348vgkvm8h8o23h9ktr68ol/pabazunotozagetufun.pdfIn PDF document text
    • https://elsadaulte.com/ckfinder/userfiles/files/26511019216.pdfIn PDF document text
    • http://mxm-hosting.nl/img/editor/file/fojoxofarepitiz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+find+element+given+ionization+energiesPDF 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_off000108a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000120bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120BB 17520 bytes
SHA-256: 31d093b2940788633fad33dff9d288ed118344c17098e538c36f5a8cefeb1ccb
font_02_sfnt_off00014d4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D4E 10900 bytes
SHA-256: d29111eb030019dc235e56b16007896a915d8e525b9f570d5de9bee1f1d03037