Malicious PDF — malware analysis report

Static analysis result for SHA-256 37daf6c039864708…

MALICIOUS

PDF

83.1 KB Created: 2021-09-18 18:47:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: aa2e2bae4c7647cfcdf4ec9f8f4212f6 SHA-1: 0a4f287563590ca0d1d032739dc4a5b3f9860449 SHA-256: 37daf6c03986470840e86adb2b11c3890c7a5da31d8d61e4397e3bb562e508fd
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which are part of a link farm hosted on disposable domains, indicating a likely attempt to redirect users to malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, identifying the document as a non-clustered link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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 https://crysiq.ru/uplcv?utm_term=advanced+mathematics+for+engineers+and+scientists+pdf PDF link annotation
    • http://gazomotor.com/allinone/file/rumupowomixar.pdfIn PDF document text
    • https://makenie.com/upload/files/86703397731.pdfIn PDF document text
    • https://ka-base.no/images_students/files/gopefikinetudowebolage.pdfIn PDF document text
    • http://katour.ru/admin/ckfinder/userfiles/files/duweg.pdfIn PDF document text
    • http://www.vinoplaza.nl/img/upload/files/12288365046.pdfIn PDF document text
    • https://quasar.mago.ro/ckfinder/userfiles/files/dofusanagirawe.pdfIn PDF document text
    • https://xn--nmqu14inmf.com/upload/files/28518924686.pdfIn PDF document text
    • https://bluza-shop.ru/content/File/85761727010.pdfIn PDF document text
    • http://hmconcretemixingplant.ru/d/files/migusujakox.pdfIn PDF document text
    • https://astefin.ro/ckfinder/userfiles/files/79413350585.pdfIn PDF document text
    • https://vettercycles.ch/userfiles/files/turabesijuzesogege.pdfIn PDF document text
    • https://sammycar.ch/sammy/sites/default/sammyfiles/newsletterfile/bunij.pdfIn PDF document text
    • https://2-view.org/home/view/public_html/ckfinder/userfiles/files/biwidukipotovinowek.pdfIn PDF document text
    • https://girisimhaber.com/uploads/file/lumokisipidejigano.pdfIn PDF document text
    • https://actionsporting.com/userfiles/files/nakezogurivome.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202109150615408207.pdfIn PDF document text
    • http://sobinco.cz/ckfinder/userfiles/files/pizixeriworo.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614289823b745---71373362286.pdfIn PDF document text
    • https://menu2uplus.com/images/file/vesibelemolivobukofow.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/16135e85f3f061---95378312982.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/7791nhajhvonaq9vac6ifrcru0/mumopobikusinufinizeji.pdfIn PDF document text
    • http://chuaphucluong.com/uploads/image/files/20574586000.pdfIn PDF document text
    • http://metaglas.kr/userData/board/file/4204937535.pdfIn PDF document text
    • https://dm288.rs/slicice/file/57262162194.pdfIn PDF document text
    • http://salondebellezaanamariaromero.es/ckfinder/userfiles/files/sajezadigixo.pdfIn PDF document text
    • http://hotel-ambassador-nice.com/upload/files/45522467398.pdfIn PDF document text
    • http://stoka-saarlouis.de/userfiles/file/fezetobobemowemuzixi.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_off0000dd39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD39 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f550.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF550 11068 bytes
SHA-256: 4e813c7f4ec100c09c974fc645a064d1d6987763ce605ae3cba416f43d6a1a00
font_02_sfnt_off00010ebf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EBF 18004 bytes
SHA-256: 3732b066a0661399699171965200a490496b422cbf832f5b4ab2911ec5c54444