Malicious PDF — malware analysis report

Static analysis result for SHA-256 f777813b2549010e…

MALICIOUS

PDF

75.6 KB Created: 2021-08-07 03:47:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ae0df5750fd668cd0d05097728c5cb3a SHA-1: 19aa9baf890600b93f8ec716d036cf9e772f76dc SHA-256: f777813b2549010e225cbda0d9733905b118f64b26ffa56304e22feb93eb3fe1
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://01host.ru/userfiles/files/35598011033.pdf In PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/f8a11425fcb70ec5346df9954d961680/62286484925.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6719a449bf---86151844437.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/16076045f00a4f---zometegupafivakujikod.pdfIn PDF document text
    • https://abeess.com/userfiles/file/gigizixajigisuw.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160784fd6e3858---vekokurorag.pdfIn PDF document text
    • http://bscartridge.com/pic/pubuxuk.pdfIn PDF document text
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/ac62c23697f4cc9447042d6550fb92b1/xiwasekamadixit.pdfIn PDF document text
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/58084455074.pdfIn PDF document text
    • http://ahsaipu.com/v15/Upload/file/2021522054302749.pdfIn PDF document text
    • http://malagi.pl/user-files/fck/file/gokuvawilisov.pdfIn PDF document text
    • http://jikaramen.com/uploads/files/podiworupuvez.pdfIn PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/gcrdict3fgcok0t5tn5rdsofl5/73714219884.pdfIn PDF document text
    • http://gphs100.com/clients/e/e3/e3ed30f4e85b1ff1e74f61348c82e8eb/File/93869721775.pdfIn PDF document text
    • http://linza-market.ru/upload/files/dijulevamorumenegawabeku.pdfIn PDF document text
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160864c981b395---36704834387.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/hr779ls1ln8l6tfkr1h21gt7h3/vupudariraxidu.pdfIn PDF document text
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/p4h6hh0b69kh1uog80jl1nqrhi/jepizefutorewaragok.pdfIn PDF document text
    • http://greece-ex.com/images/blog//file/vubakabezokebux.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b7ea1ae1674---14447946247.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/c75c20b0dcc8e739b887564df47a451b/daniviropufaralemobe.pdfIn PDF document text
    • https://majorsagilekvaros.hu/uploads/file/fepijivixazegagidawegem.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c8e48a1ba7a---61906620578.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=carnegie+learning+algebra+1+volume+1+answer+keyPDF 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_off0000c3ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3AE 11036 bytes
SHA-256: 299552ad0ebf418fbee5aa94150a4ce08f0c83583135c62e167cff743d04b144
font_01_sfnt_off0000dd6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD6F 16796 bytes
SHA-256: 9f9d4d068591263e537562efbe05cf30a9c46fdf2e12bc55d9fa7ff8fa8be143
font_02_sfnt_off00010842.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10842 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1