Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e9b1e97f11c6525…

MALICIOUS

PDF

82.0 KB Created: 2021-09-11 18:59:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4cd73c470390b5425e86aab9bcfae0ac SHA-1: eaab6617a9e34b9b1b2cd2a3eb1025fd99ee5c4d SHA-256: 4e9b1e97f11c65259919604051d06a8cad6fbf183f2edfeb65f49dadafc2d8ac
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to disposable hosting and are structured as a link farm, a common tactic for phishing or distributing further malware. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this. No scripts were extracted, but the overall structure and URL patterns strongly suggest a malicious document designed to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://infrive.ru/uplcv?utm_term=fallen+in+love+lauren+kate+pdf PDF link annotation
    • https://singhaniabrothersltd.com/ckeditor/ckfinder/userfiles/files/zuserisegavup.pdfIn PDF document text
    • https://thefencedocumentary.ca/adminfiles/file/visibisuniguzurofi.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1612f997f2c8bb---nenime.pdfIn PDF document text
    • http://bluestandard.pl/ckfinder/userfiles/files/vawamaxogusakasutemabewo.pdfIn PDF document text
    • https://accu-split.com/userfiles/files/xinusebebiwisitufod.pdfIn PDF document text
    • http://hangtatmj.com/userfiles/83245703951.pdfIn PDF document text
    • http://tiendanatacion.com/noticias/files/mowadise.pdfIn PDF document text
    • http://metalzilembo.it/userfiles/files/pasaw.pdfIn PDF document text
    • https://dveropolis.ru/upload_picture/wuvet.pdfIn PDF document text
    • http://ecoaga.com/documentos/file/81146639203.pdfIn PDF document text
    • https://freebcard.com/ckfinder/userfiles/files/89049500618.pdfIn PDF document text
    • http://marymo.ru/uploads/files/17077476248.pdfIn PDF document text
    • https://nsck-cykelmotion.dk/ckfinder/userfiles/files/90241258989.pdfIn PDF document text
    • http://colafranceschi.it/userfiles/files/bidewuz.pdfIn PDF document text
    • https://erdenetpost.mn/userfiles/files/97505574656.pdfIn PDF document text
    • https://am-system.eu/ckfinder/userfiles/files/45384966949.pdfIn PDF document text
    • http://mega.kz/media/upload/files/gudejelovuzonufarudavi.pdfIn PDF document text
    • http://konditsionery-reutov.ru/upload_picture/file/43548306882.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131bea189fff---fasojavezugetiba.pdfIn PDF document text
    • https://autopits-directo.migrupoq.com/ckfinder/userfiles/files/fosipatalukujezakavovaxo.pdfIn PDF document text
    • http://www.ags-sib.ru/ckfinder/userfiles/files/63803636142.pdfIn PDF document text
    • http://familiegravesen.dk/ckfinder/userfiles/files/44070957960.pdfIn PDF document text
    • http://lawyergz.net/uploadfile/files/bufigulafetipex.pdfIn PDF document text
    • https://lucky-erotic-massage-bucharest.ro/ckfinder/userfiles/files/bikisupujanemimoxigebit.pdfIn PDF document text
    • http://uran-berlin.com/userfiles/file/24112190633.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_off0000df9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF9E 10556 bytes
SHA-256: df089a0351d6085e911b4c60be33dda2e5bd9347d642dfd0decfe5919c5bbed1
font_01_sfnt_off0000f7c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C1 16428 bytes
SHA-256: 685a6382dbd2aca4c872ca4b8944f75b481cbd352aa5241cc4e2640e3613df2e
font_02_sfnt_off00012221.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12221 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1