Malicious PDF — malware analysis report

Static analysis result for SHA-256 4be743b6c4afa89c…

MALICIOUS

PDF

75.7 KB Created: 2021-09-11 18:42:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 20c0db0ab8ea945d917494304691cf9a SHA-1: b268bae80198a9537dddde7522707e2dc5e014ae SHA-256: 4be743b6c4afa89cec2bab132433017e28e81e71e029a2863d9443ec81053b08
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of embedded JavaScript and a large number of external URIs, many pointing to PDF files on various domains, suggests a phishing or malware distribution campaign. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a link farm designed for SEO manipulation or to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://clickbox.ro/images/file/7248716043.pdf In PDF document text
    • https://verandapattaya.com/userfiles/files/gakedomituv.pdfIn PDF document text
    • https://hygradeinsulators.com/images/uploads/file/ragezibazenubuzi.pdfIn PDF document text
    • https://perfumes.dropship-tracking.com/userfiles/files/52255220732.pdfIn PDF document text
    • http://haraj-alqunfudhah.com/userfiles/file/85574440221.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/f74744337591b755414cbff358ab78c1/95855741851.pdfIn PDF document text
    • https://zhansq.cn/upload/file/sugogeporadog.pdfIn PDF document text
    • http://philipp-haberland.de/images/upload/file/96996789754.pdfIn PDF document text
    • http://gpkoaee.ru/ckfinder/userfiles/files/tupeguwisinonusatobupeket.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613b040cd3f88---xodazitowepasarugutasowad.pdfIn PDF document text
    • http://www.louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/53416911339.pdfIn PDF document text
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/wumasorupaxoraz.pdfIn PDF document text
    • http://robertwestlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/10514375971.pdfIn PDF document text
    • https://everestart.com/images/stories/file/walemipifipifugaxomijawil.pdfIn PDF document text
    • https://unitytradecapital.com/ckfinder/userfiles/files/muvajubaparexinames.pdfIn PDF document text
    • https://aljazeerahdrilling.com/userfiles/files/11351202440.pdfIn PDF document text
    • https://cartolmania.it/file/lirejorujidodesudavusu.pdfIn PDF document text
    • http://tensoinox.com/userfiles/files/zejomevoxufu.pdfIn PDF document text
    • http://fatename.com/uploads/files/202109051822458848.pdfIn PDF document text
    • http://1544-7419.net/upload/fckeditor/file/97672810093.pdfIn PDF document text
    • https://www.nitdgp.ac.in/uploads/userfiles/files/90192891568.pdfIn PDF document text
    • http://be-now.pl/userfiles/file/weduxalaminakenoxibuz.pdfIn PDF document text
    • http://langmoon.jp/js/upload/files/xifiwixogobokelatixoze.pdfIn PDF document text
    • http://boathousebrokerage.com/userfiles/file/pezori.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=bunny+vpn+proxy+free+vpn+master+with+fast+speedPDF 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_off0000c0cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d8de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8DE 17784 bytes
SHA-256: bd1ff79a5fadf583b29593f397bbc108ac1a0b6b775798922e7c57f2408a03aa
font_02_sfnt_off00010704.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10704 11236 bytes
SHA-256: 2c4db21b8bd23e1b5d691da1dc6e779eddef9525cb688214e8059e6bdd61dfc3