Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d4946f73c027de1…

MALICIOUS

PDF

95.9 KB Created: 2021-07-03 19:32:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: aa43591fba8e109dcc2859d22ea3f3df SHA-1: 62200804fd85ff311f06fa62ef5870c341bf434f SHA-256: 8d4946f73c027de162ff35251275e6bfd77f1251b369a1f7a49da477adb554ff
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to websites hosted on compromised Content Management Systems (CMS), as indicated by heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM'. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or SEO spam. No scripts were extracted, but the document's structure and embedded URLs are sufficient to infer its malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

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://nomylo.ru/uplcv?utm_term=how+to+make+a+private+unturned+server PDF link annotation
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/vkvlrdvh59v5moo77n36hjtt5n/wogoduker.pdfIn PDF document text
    • http://agendatourvietnam.com/hinhanh/file/jawizupumanemanupezodono.pdfIn PDF document text
    • https://sensiblemachines.com/ckfinder/core/connector/php/files/57329177798.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609114c271bb6---befenosomolagawidipejo.pdfIn PDF document text
    • http://school19-zav.ru/userfiles/file/27007229031.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160dfdeb82800f---nebutepemaju.pdfIn PDF document text
    • http://divorce-difficile.fr/userfiles/file/kowijipaviwodig.pdfIn PDF document text
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/14420379cb22c076710568f38d2b465d/kuxawavazepulen.pdfIn PDF document text
    • http://qkmedica.com/uploads/userfiles/file/belimuputesana.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c2d6550cc2d---linuxowuwutatinonorapuxum.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608ed24d2f5de---wutufujemigu.pdfIn PDF document text
    • https://samsungvrvklima.com/upload/ckfinder/files/80245125212.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c0d08730dc3---xegonarofake.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/0cbhvh34hmeqgtsigdigc8qdv5/46344019121.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608dc87bcd5ca---21438871518.pdfIn PDF document text
    • https://www.zaantraining.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16094b49b4a955---14819705915.pdfIn PDF document text
    • http://uleshuzatshop.hu/files/file/rudevowinefagedu.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16087cae946450---vumasilifajabilu.pdfIn PDF document text
    • https://emauto.lv/index/images/up/file/defexenunuweze.pdfIn PDF document text
    • http://dribblebar.pl/userfiles/file/zudavowulakigepexebotimo.pdfIn PDF document text
    • http://reanda.com/jingkelun/userfiles/files/20210622160058.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606f8a4e2a60c---68750445313.pdfIn PDF document text
    • http://accronline.com/userfiles/file/juroba.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/90325986002.pdfIn PDF document text
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/0f878a2942b13bad0c86f8a91beab259/38117714314.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3e5566be2b---timidim.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160773a4fbf2f9---sunamomozixak.pdfIn PDF document text
    • 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_off00010f6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F6C 19052 bytes
SHA-256: f8d795129efbbad98fe1dda1fd468794a29e09c9512def8ed746a11cc5731610
font_01_sfnt_off000140ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000158e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x158E1 10844 bytes
SHA-256: 38809aa1618934202a00859489dd7b4fa5c29f3d261117bf6de4d0b554dd0c33