Malicious PDF — malware analysis report

Static analysis result for SHA-256 7becf23c5d47b42b…

MALICIOUS

PDF

108.2 KB Created: 2021-10-05 02:32:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: adc152a23a5806489f3b83fb583669d4 SHA-1: 27bbaa6045b3bf53e035744f62ea5230ca75ac5f SHA-256: 7becf23c5d47b42b87364c14f0a11b9aeb29ce6f8c9162f1d5dbc1c7776d99dc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The file was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated, preventing analysis of its specific content, but the presence of numerous external links strongly supports the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9931

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 https://onderdurdu.com/upload/ckfinder/files/lifegefivademax.pdf In PDF document text
    • https://avistravel.ro/userfiles/file/nuxeseluzunifemumadi.pdfIn PDF document text
    • http://grandp.ru/userfiles/file/98918765548.pdfIn PDF document text
    • http://bobmeetin.com/media/galleries/files/raxawizepapusaj.pdfIn PDF document text
    • https://myparrotfood.com/user_files/files/tijisenufaxabaw.pdfIn PDF document text
    • http://imhang.com/fckeditor/userfiles/image/sirufakurusozan.pdfIn PDF document text
    • http://good163.cn/Uploadfiles/files/22576586206.pdfIn PDF document text
    • http://vdadanang.vn/app/webroot/assets/files/6152306995.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16153af99243e1---supajupilamoxo.pdfIn PDF document text
    • http://cpk.by/ckfinder/userfiles/files/32636047092.pdfIn PDF document text
    • http://druckmaschinenservice.com/uploads/fce/files/16847155754.pdfIn PDF document text
    • http://take114.kr/FileData/ckfinder/files/20210907_611478ACF0CE27E8.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/f283f7fcd1a66ff1d66a72d7265feec7/pazisajebatakatusek.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614beff8b576c---rajunekitobararije.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/6daca236f4b7edc429f6094749efccd8/vinip.pdfIn PDF document text
    • http://talcmanagement.com/uploaded_files/userfiles/files/rikulade.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16152fdef7aff7---zivogak.pdfIn PDF document text
    • http://infinijewelry.com/userfiles/file/27912074844.pdfIn PDF document text
    • http://wcsps.com.tw/ckfinder/userfiles/files/lozumaxejidufumebif.pdfIn PDF document text
    • https://pirkitpadangas.lt/ckfinder/userfiles/files/janitufopofido.pdfIn PDF document text
    • http://gazdalkodjokosan.hu/img/userfiles/file/17413776933.pdfIn PDF document text
    • https://malmospelmanslag.se/userfiles/file/53933368637.pdfIn PDF document text
    • http://rungruangsteel.com/public/upload/userfiles/files/walupedirudalituzil.pdfIn PDF document text
    • https://volpatoebrum.com.br/_common/admin/scripts/ckfinder/userfiles/files/mabinetidikagixixajur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=fairy+tail+meaningPDF 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_off00013923.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13923 23428 bytes
SHA-256: d6d860509deadda05438b1459ac4a173a5da8c7eb32f46431fb1024e3cdcd341
font_01_sfnt_off00017504.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17504 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00018d1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18D1B 10252 bytes
SHA-256: fe058df94b6faacad951a43cee988a145ce5d185f3697fc3b673a0f1a55111ce