Malicious PDF — malware analysis report

Static analysis result for SHA-256 650c21b68f4f0cc6…

MALICIOUS

PDF

87.0 KB Created: 2021-09-04 19:27:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: be5fd0f16cc302c3d6ad7f6545bacd9b SHA-1: 58c327027cb1948569daa0c1fa6de4242726537b SHA-256: 650c21b68f4f0cc67323c8d41280d89c4b2c9f4f2f2b6aa824502f1adbf3f927
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 potentially compromised WordPress sites, indicating a link farm designed to redirect users. Heuristics suggest it's a link farm on disposable hosting, and ClamAV detection confirms its malicious nature. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://tksvolga.ru/userfiles/file/saritatukujubixu.pdf In PDF document text
    • http://karlsbach.de/userfiles/files/posesarabamakabomabojejax.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/bku48g6c9lq4kkndaqenldvk4o/naxilevifori.pdfIn PDF document text
    • https://sportnazona.bg/f/uploads/files/faludojikipixe.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/35afe4bd3b43de113beda49ad766de5f/90328997079.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608de66a47596---pabirusefapewux.pdfIn PDF document text
    • http://raiders71.com/clients/4/41/4134020f2f298c111575624a380fabfc/File/fabuvebipa.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/886524f60f1841b94a175bb5445cf7d7/8890115693.pdfIn PDF document text
    • http://timandlor.com/userfiles/file/9161906550.pdfIn PDF document text
    • https://ddshower.com/ckfinder/userfiles/files/kirajiwazogarujozig.pdfIn PDF document text
    • https://stillwaiting.org/userfiles/file/jaxuwiseju.pdfIn PDF document text
    • http://fotografiafrancescosomma.com/userfiles/files/refuvivisuf.pdfIn PDF document text
    • https://alice-immo.com/userfiles/file/bewazapaxidego.pdfIn PDF document text
    • https://fishuntpesca.it/file/29313398494.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/3323bf1f882a6ce0e8099e1767eb3225/nukenazusawezedukezababu.pdfIn PDF document text
    • https://bloomland.com/sites/bloomland.com/files/matanerunabo.pdfIn PDF document text
    • https://ceccarbotosani.ro/userfiles/file/vavilanivateso.pdfIn PDF document text
    • http://tdvvietnam.vn/webroot/img/files/sukujix.pdfIn PDF document text
    • http://ledspectrumthai.com/ckfinder/userfiles/files/mebonutowawu.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/c18232b8ffdb4ef799fd0214006b2591/bojoruzawalowowaneweg.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/t227e2qtvdhsbovqdot4s8i4n6/wikiximizumotavu.pdfIn PDF document text
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/43097943201.pdfIn PDF document text
    • http://pantryscan.com/123cars/imagefck/file/47651014187.pdfIn PDF document text
    • http://megat.pl/uploaded/fck_files/file/90435544675.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=topic+sentences+examples+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_off0000ef43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF43 17984 bytes
SHA-256: a5642c674a4ecce71fc3332829c5bfd2f0d9e0f3c06a6efa6df9a5410479859d
font_01_sfnt_off00011de4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000135fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135FB 10744 bytes
SHA-256: 88e86e6637e3e2fcab5df142168d49c6c1268c82bbbef6d3d9874b64ce461541