Malicious PDF — malware analysis report

Static analysis result for SHA-256 da8cfbb769c39242…

MALICIOUS

PDF

73.5 KB Created: 2021-09-26 23:24:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 8d26789111b888e1b96d49f628be333b SHA-1: 622c750e79b2b12b96486a1320052263ee677460 SHA-256: da8cfbb769c39242ec5139953eb617d6a41e5025bd2a01385a3a905311a6138f
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further support the conclusion that this document is designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://screen.by/images/file/82874983491.pdf In PDF document text
    • http://sentezetutmerkezi.com/upload/ckfinder/files/nefugewimuvapitudipegopo.pdfIn PDF document text
    • https://jv-cms.crazy-jessie.nl/uploads/files/41717279073.pdfIn PDF document text
    • http://ms-krmelin.cz/app/webroot/files/files/97765531944.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/0nf2l62js5ctpmetsfl27q2eu3/60898831318.pdfIn PDF document text
    • http://max-metal.pl/gfx/file/8475153375.pdfIn PDF document text
    • https://flims.atelierleuthold.ch/userfiles/files/80405206227.pdfIn PDF document text
    • https://learnrkbin.jugalbandiresearch.com/ckfinder/userfiles/files/budiwozo.pdfIn PDF document text
    • http://www.otevrenysklep.cz/ckfinder/userfiles/files/81045138254.pdfIn PDF document text
    • http://saipanbooking.com/FileData/ckfinder/files/20210907_A6B24F6CFA131559.pdfIn PDF document text
    • http://www.neoneofitou.com/ckfinder/userfiles/files/81288479817.pdfIn PDF document text
    • http://letnaterasa.customreal.sk/data/files/24488121563.pdfIn PDF document text
    • https://plantbiochem.com/ckfinder/userfiles/files/17545456814.pdfIn PDF document text
    • https://www.sibirprokat.ru/ckfinder/userfiles/files/zopiwosiliwenivexijus.pdfIn PDF document text
    • http://topbuild.net/content/xuploadimages/file/92584840019.pdfIn PDF document text
    • http://kagoshimakojintaxi.com/userfiles/file/84739077529.pdfIn PDF document text
    • http://fluitec.fr/ressource/site-image/files/lazapesekotuse.pdfIn PDF document text
    • http://saktigroup.in/uploads/23530189214.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/161417dd319dbc---57297373635.pdfIn PDF document text
    • http://aibasavar.edu.bd/app/webroot/ckfinder/userfiles/files/xusor.pdfIn PDF document text
    • https://canionglobal.com/FCKeditor/file/81574184352.pdfIn PDF document text
    • http://wonderful-foods.net/userfiles/file/529659240.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=six+pack+photo+editorPDF 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_off0000b3d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cbec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBEC 10560 bytes
SHA-256: c731070a93fa7d9870f5d1976f0207b7db070d5db5cef58fdbbac1b4f8f105ee
font_02_sfnt_off0000e42d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE42D 20460 bytes
SHA-256: 332ed93622f17652df8770eb29b3cb3bb81f93ab79809142870b9e57e821474e