Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b0698b202cf8d90…

MALICIOUS

PDF

81.1 KB Created: 2021-09-23 10:08:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 891c5331d3035ab043045ce6272f4b03 SHA-1: 0cc84a1a15e47114f3fb0af5da607c2a67aea278 SHA-256: 8b0698b202cf8d903095c598a80bcefaf85fc907ab82bfc0887a26dc77dc569b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier with high confidence. It contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, suggesting a phishing or malware distribution campaign. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a deliberate attempt to create a large number of links on low-reputation hosting. No scripts were extracted, but the overall structure and heuristics strongly indicate a malicious intent to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://drafthe.ru/uplcv?utm_term=connect+wireless+keyboard+to+firestick PDF link annotation
    • http://jucal.es/images/file/48080119575.pdfIn PDF document text
    • http://kunbot.com/upload/files/wunawile.pdfIn PDF document text
    • http://gzmzwl.com/Uploadfiles/files/28510337912.pdfIn PDF document text
    • http://rbc-bezorgdiensten.nl/upload/pugorekuj.pdfIn PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/44695848905.pdfIn PDF document text
    • https://smartcrm.cloud/upload/files/feputol.pdfIn PDF document text
    • http://evolutionchonburi.com/userfiles/files/45097800859.pdfIn PDF document text
    • http://materialdeestudo.top/userfiles/files/kozowofedav.pdfIn PDF document text
    • https://taipeitccia.org/CKEdit/upload/files/fijutofibaludawaz.pdfIn PDF document text
    • http://mkconline.com/landmark/ckfinder/userfiles/files/gujezitumujasejonetosi.pdfIn PDF document text
    • https://igraonica.me/userfiles/file/lojofifazenaka.pdfIn PDF document text
    • http://barrybusiness-crm.com/ressource/devis-photo/files/sixatidokuw.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614bc642b154a---raterejopok.pdfIn PDF document text
    • https://photopoligrafic.ru/ckfinder/userfiles/files/mutaj.pdfIn PDF document text
    • https://elegune.net/files/galeria/files/85991624297.pdfIn PDF document text
    • http://tubietelbar.hu/uploadfile/zabovek.pdfIn PDF document text
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/86734627547.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/webevikafiritepe.pdfIn PDF document text
    • http://hstairan.com/FCKeditor/editor/filemanager/connectors/php/userfiles/file/63704554364.pdfIn PDF document text
    • https://wonwon.taipei/photo/file/kuzowiga.pdfIn PDF document text
    • https://jecoexports.com/ckfinder/userfiles/files/94425960203.pdfIn PDF document text
    • https://implantologie-deva.ro/app/webroot/files/userfiles/files/besuvebo.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/vemukugorisobutadafiku.pdfIn PDF document text
    • http://epmachine.ru/d/files/52719890150.pdfIn PDF document text
    • http://zs.tom.ru/jsplugins/ckfinder/userfiles/files/48100002601.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_off0000d8c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f0da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0DA 17188 bytes
SHA-256: 230c7f38a9a269b70997a4da950f319d9fb7d24e403d6b3c8ba0286360ee2dad
font_02_sfnt_off00011d52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D52 10932 bytes
SHA-256: 245abc8ca22e1b986fedc5db93e34ba3234441fcbf8f00b7ee94952d5b9f15ea