Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4420069d4e27ccd…

MALICIOUS

PDF

69.0 KB Created: 2021-09-25 12:53:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4d4e351bc471476c604ff2fbcc729f62 SHA-1: 5f2f9ed075b805857c914adae633c6f036acffc5 SHA-256: f4420069d4e27ccd60d609aedab7d68f7599c98e791b0355fbf6f0eaca597d8d
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV detection, indicating malicious intent. The presence of numerous embedded URLs, many pointing to potentially disposable domains, suggests a link farm designed to redirect users to malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically highlights this behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://theclubburger.com/uploads/files/sapugefogufoti.pdf In PDF document text
    • http://chothuexeninhbinh.net/data/dulieu/files/91373359951.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1613aed41b280c---baxomexasud.pdfIn PDF document text
    • http://aguito.madteam.net/ckfinder/userfiles/files/monekenu.pdfIn PDF document text
    • https://curewelldiabetes.com/userfiles/file/wegonoveg.pdfIn PDF document text
    • http://ilonew.tasksplan.com/ckfinder/userfiles/files/dabetegarowelanemegofose.pdfIn PDF document text
    • https://global-brand.net/userfiles/files/95962994042.pdfIn PDF document text
    • http://podwierzba.eu/ckfinder/userfiles/files/67992443301.pdfIn PDF document text
    • http://boldogelet.hu/media/30942793411.pdfIn PDF document text
    • https://verner.lt/images/files/68844875899.pdfIn PDF document text
    • http://toyteepee.com/uploadfiles/file/210903155021067407cmrpho.pdfIn PDF document text
    • https://www.retake.dk/ckfinder/userfiles/files/65247921356.pdfIn PDF document text
    • http://chanhbon.vn/media/ftp/file/41236274288.pdfIn PDF document text
    • http://ekhoron21.mn/uploads/files/49636259857.pdfIn PDF document text
    • https://goodluckfishing.com/ckfinder/userfiles/files/danixutotelijotov.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ebf6e6ecf6---tedupif.pdfIn PDF document text
    • http://ap116.ru/userfiles/file/vazazasameji.pdfIn PDF document text
    • http://sjccgy.com/userfiles/file/zuritexabalisomebewapik.pdfIn PDF document text
    • https://rougezenekar.hu/files/file/doguvelegazepiwigepir.pdfIn PDF document text
    • https://jnvhardoi.org/ckfinder/userfiles/files/fadisevijefamuvirezu.pdfIn PDF document text
    • http://hosungtour.com/FileData/ckfinder/files/20210925_76C82009B5380573.pdfIn PDF document text
    • http://sdes.in/uploads/kurivuwijexotuwaf.pdfIn PDF document text
    • http://oxigensupplies.com/shipinc/userfiles/files/kubanimasewoset.pdfIn PDF document text
    • https://eqonetech.com/upload/userfiles/files/lilanis.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=naruto+games+offline+androidPDF 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_off0000af86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c798.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC798 15168 bytes
SHA-256: 17403b559574f522d9f17bbca450a2bc711e428b8bfe31cc72ece5d98386c644
font_02_sfnt_off0000edae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDAE 10772 bytes
SHA-256: b51e375b7455c00639704c77b4321e6ce082a67f20723f97dc15107794154af2