Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ad4692a2e3ceec5…

MALICIOUS

PDF

84.2 KB Created: 2021-09-10 20:57:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3fa0bf50688c194a49e7645616721988 SHA-1: b2141b34908c87295cda676737d1e688a61e9ad1 SHA-256: 4ad4692a2e3ceec55b023f35ca0aa7a4f4d007e8802cacef867e3cfb6227a144
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by multiple heuristics as a link farm, with many URLs pointing to potentially compromised or disposable hosting. The ML classifier and ClamAV also strongly indicated maliciousness. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the presence of numerous external links suggests an attempt to redirect users to malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://intemhathanh.com/img_duhoc/files/luzuniwuxo.pdf In PDF document text
    • https://gotoko.com/cmsv2/upload/files/97847220593.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/20925133062.pdfIn PDF document text
    • http://studioferrato.it/userfiles/files/46156410844.pdfIn PDF document text
    • https://riolospettacoli.it/filesUploads/file/74313427384.pdfIn PDF document text
    • https://banerjeetourspecial.in/ckfinder/userfiles/files/surigininivunonevukak.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/99c59f563ef0ed5809ff0738a7461d38/dikoremet.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/161323244a4cca---wetadosimozobum.pdfIn PDF document text
    • https://suacuacuontoanphat.com/upload/files/9821737757.pdfIn PDF document text
    • https://signos.larrialdiak.es/files/galeria/files/weriva.pdfIn PDF document text
    • https://datatalk.ilvzhou.com/upload/files/2021/09/202109051134326993.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16139c2968b724---45212673094.pdfIn PDF document text
    • http://arci-mp.fr/admin/File/695689996.pdfIn PDF document text
    • http://ambulatorioveterinariocamali.com/userfiles/files/mupakugazanazedevakumuf.pdfIn PDF document text
    • https://learningsolution.ca/userfiles/files/lezed.pdfIn PDF document text
    • https://www.displaysdirectaustralia.com.au/application/third_party/ckfinder/userfiles/files/27816328191.pdfIn PDF document text
    • http://tajeer.co/userfiles/file/ruludubux.pdfIn PDF document text
    • http://abwingsjanaf.com/uploads/files/nasugolowux.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134a46332e70---95912017743.pdfIn PDF document text
    • http://transbur.ru/admin/ckfinder/userfiles/files/najilakikudiwe.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161311e8105d51---21531765163.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=ratatouille+movie+watch+onlinePDF 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_off0000e38b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE38B 10524 bytes
SHA-256: eab84a90be5291f92e85f6878d96a9f3e3b5202eb928e96ae853a808657ac0ee
font_01_sfnt_off0000fb69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001137b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1137B 18740 bytes
SHA-256: c9cdf4ea91dbc388d20948a033ffe25ced413aa97ba8c0f8a2e7286e37bdafd5