Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7af9123b4eaa91e…

MALICIOUS

PDF

87.0 KB Created: 2021-07-21 06:44:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f695308c05c33c97b0c709d1f2fe8cdd SHA-1: 3d1b306d10725f43cce3b370cd55d1f82412c864 SHA-256: b7af9123b4eaa91ea6b1af8dda98d66cc7ee1957d936e96a0d53a586f9aa8792
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 compromised WordPress sites. Heuristics indicate this is a link farm designed to direct users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://ukdirectremovals.com/wp-content/plugins/super-forms/uploads/php/files/dd0a219f0a8a678828bf2ec5f9633f75/poluvolozikasuropur.pdf In PDF document text
    • http://divodizain.ru/ckfinder/userfiles/files/10994027497.pdfIn PDF document text
    • http://kondicionery-vidnoe.ru/upload_picture/file/kudokejijimosevoxojijuwe.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/3e1629a837a2595cffafa3d1cc9443a4/wanogevove.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/160bd19f57a0a7---rilelimawizodo.pdfIn PDF document text
    • http://klasykarozrywki.pl/public/images/fck/file/87079465265.pdfIn PDF document text
    • https://edoxmarketing.com/wp-content/plugins/super-forms/uploads/php/files/4qfqsbmkudo4okb9beavvskoof/67310837604.pdfIn PDF document text
    • https://media-get.com/userfiles/files/vobajo.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160757ee9dd650---37897073168.pdfIn PDF document text
    • https://bandai-k.com/userfiles/file/40894195906.pdfIn PDF document text
    • http://abimobiliare.pl/pliki/File/zamafurekuwo.pdfIn PDF document text
    • https://sklep-pinokio.pl/web/uploads/files/69751386232.pdfIn PDF document text
    • http://www.anieliasfx.com/uploads/textareas/file/40968271543.pdfIn PDF document text
    • https://fallsplat.se/file/xipuzifim.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a8bfc45b68f---40547553368.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/66959b6cd40b66134c11310dbff860b5/8021168952.pdfIn PDF document text
    • http://fogathajtohirek.hu/fckfiles/file/78608497974.pdfIn PDF document text
    • https://efficientinfocomm.com/ckfinder/userfiles/files/58099606109.pdfIn PDF document text
    • http://igorodstore.ru/files/userfiles/files/nejir.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609ac61137d63---xepipuxaburado.pdfIn PDF document text
    • http://bsbcarpet.com/userfiles/file/95404752750.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=to+stick+onPDF 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_off0000f322.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF322 9840 bytes
SHA-256: 3d16919d8e468d75ecf01c2d6b1968729f3a734fa97c4cb4970708a735e174e8
font_01_sfnt_off000108ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000120fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120FC 17692 bytes
SHA-256: 92595cd31573d60698b1128b32be12e446f69c582085496aa498e46a4a3d520f