Malicious PDF — malware analysis report

Static analysis result for SHA-256 05c9031bd0e0f68f…

MALICIOUS

PDF

88.5 KB Created: 2021-09-18 08:49:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ac04fc5a49f224f954ea65a2ec7a9a74 SHA-1: 11f7dd2551ce19384d102fd6ab4663007f6f89e7 SHA-256: 05c9031bd0e0f68fe4eec3f787c0b84d7e37c7caf481041f476e321ce077ec2b
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many pointing to disposable domains, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for distributing further payloads or conducting phishing. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a malicious document designed to redirect users to compromised or malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://crysiq.ru/uplcv?utm_term=fifty+shades+of+grey+full+movie+watch+online+movierulz PDF link annotation
    • http://xfswchem.com/upload/files/jenuxizus.pdfIn PDF document text
    • http://ellenia3.eu/userfiles/files/37507454318.pdfIn PDF document text
    • https://istruttorecinofilo.it/userfiles/file/rasisujijufog.pdfIn PDF document text
    • https://oolong-dining-co.com/webroot/editor-uploads/files/94758916188.pdfIn PDF document text
    • https://yennenga.org/business_school/uploads/file/93107573813.pdfIn PDF document text
    • http://uts.edu.co/portal/app/ckfinder/userfiles/files/68457862344.pdfIn PDF document text
    • https://maytinhdalat.vn/images/uploads/files/66433394250.pdfIn PDF document text
    • http://ambulatorioveterinariopisillibertozzi.eu/userfiles/files/24912156132.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/f93hpgjnbict9fkirocc8ojkc2/laputijovupusuxabekunux.pdfIn PDF document text
    • http://csc010.com/userfiles/file/20210915153427_80twbz.pdfIn PDF document text
    • http://baocaosuhoatoc.com/luutru/files/46399348139.pdfIn PDF document text
    • http://arcenevents.nl/site/upload/files/rufanenejalizuradinet.pdfIn PDF document text
    • http://sarkar.ie/userfiles/file/fumatanezixaxes.pdfIn PDF document text
    • https://brune-schmuckwerk.de/ckfinder/userfiles/files/15507072050.pdfIn PDF document text
    • https://adian.eus/files/galeria/files/51565567339.pdfIn PDF document text
    • http://neza.cz/UserFiles/File/4888577405.pdfIn PDF document text
    • https://sharpconsulting.us/app/webroot/ckfinder/userfiles/files/53567883967.pdfIn PDF document text
    • http://ck-kutnahora.cz/gais/image/file/41417324584.pdfIn PDF document text
    • http://mylivediamondinventory.com/uploads/files/finuxupidugo.pdfIn PDF document text
    • https://trainova.com/userfiles/file/48219763546.pdfIn PDF document text
    • http://grafosaleservice.cz/images/fck_editor/file/53740803156.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613643087e42d---wegijetuf.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/86049212313.pdfIn PDF document text
    • https://sieseam.org/userfiles/files/5398803221.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_off0000f3c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010be0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BE0 11324 bytes
SHA-256: b50604d5664761736c9e1935283376f9d6de8605caf2f9829823c7a17df51836
font_02_sfnt_off00012637.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12637 17904 bytes
SHA-256: e04e885cb03e773f1ffdf752d2b2084ff2cedf9a511deb254dabb6fb152aa6d1