Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbd343a9d4c840d3…

MALICIOUS

PDF

100.7 KB Created: 2021-09-04 08:55:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: bb3d9f2ac8a3aadda6ece00586132d04 SHA-1: 46ac67752b50120185847b52d2b602e988bc6267 SHA-256: fbd343a9d4c840d304c1963444ce70c42d6928ca0aa14323e995134bc70dcd6e
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and links to compromised CMS upload storage, suggesting it functions as a link farm to distribute malicious content. The PDF structure itself does not contain readable content, but the presence of multiple external links points towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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 http://www.leasebridge.com/CKUPimg/files/39085207257.pdf In PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076965641e81---fawudiwot.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/e25b2270101b38b24ed1d8921dce0125/74843050171.pdfIn PDF document text
    • http://romento.com/uploaded_files/userfiles/files/35461011766.pdfIn PDF document text
    • https://bcm.es/files/galeria/files/dolimewukirexexoki.pdfIn PDF document text
    • http://cnmrobotics.com/files/files/17834806746.pdfIn PDF document text
    • http://www.zima.snowcat.pl/admin/ckfinder/userfiles/files/fidabimidizov.pdfIn PDF document text
    • https://ph2020.org/FCKeditor/file/zuzuxa.pdfIn PDF document text
    • http://maysoi.com/hinhanh_fckeditor/file/kalarebex.pdfIn PDF document text
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/tf98dsrpik5vfqfm8rere8nmj3/2106344977.pdfIn PDF document text
    • https://manuscripthandler.com/userfiles/file/64958535824.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160b412125100c---kapimelaw.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/dee5fce4619a4a9304d62e3b8980ca27/dejekezo.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/47e2f2bc075a1483195dd7feee3d4bbd/11691838808.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/2dfnehn9ah65gh55fom0o31k26/muwadojuzanatolopirumiza.pdfIn PDF document text
    • http://studiocalcinoni.com/userfiles/files/58008217542.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160e431b4a8046---velafovulosijevepuzidira.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/0pa33uhqrp9o23q5feta6npt7t/widofukupusade.pdfIn PDF document text
    • http://brixtontaxi.com/survey/userfiles/files/bimimozujuvike.pdfIn PDF document text
    • http://frangarcia.eu/upload/file/rexokololedi.pdfIn PDF document text
    • http://evergladesharvesting.com/ckfinder/userfiles/files/13187244936.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608602d76b601---48114983450.pdfIn PDF document text
    • https://mcq-exambd.com/app/webroot/ckfinder/userfiles/files/bizafovuv.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/8c5b78c2fef03123b3eff2e227857a98/6045721836.pdfIn PDF document text
    • http://talani.nl/userfiles/image/file/tobubuxodede.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=consumer+protection+act+case+studies+pdfPDF 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_off000122c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122C0 18848 bytes
SHA-256: 708a3449f45a69b82a9ef8db10c7ce169af4d112b99c6c9c33ffeb7fb2a47f0a
font_01_sfnt_off00015320.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15320 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016b37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16B37 10864 bytes
SHA-256: 6d0c74806891a39f66729c824282eb5c16c061e737eb84d7cfe0e875dea6ec48