Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4de2fba648d576e…

MALICIOUS

PDF

77.9 KB Created: 2021-09-19 03:18:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c18feb04927a26209ec4a698fcb2abab SHA-1: 36bd4753fbf73d036418449d0a03d32aff18a690 SHA-256: c4de2fba648d576e8d604ff87775292205fce1b12e6a187f2e51e68600d0c8cc
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and multiple links to external PDF files hosted on compromised websites, indicating a phishing or malware distribution attempt. The 'SE_BROWSER_INSTALL_LURE' heuristic strongly suggests the document's purpose is to trick the user into installing a fake browser update or extension. The ML classifier and ClamAV detection further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16131a43f7e249---46717952886.pdf
    • http://nitexprofi.cz/userfiles/file/40385572153.pdf
    • https://pinpointfeedtech.com/ckfinder/userfiles/files/46942626498.pdf
    • https://melz-feu.ru/upload/novugireno.pdf
    • http://www.benyowsky.com/resources/files/4012393068.pdf
    • https://ntiverification.com/userfiles/file/tusobenonekemagapegono.pdf
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135ca7f3f889---83729745733.pdf
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/6478ed2db734f3aa3bf1126aeafd6aa5/76800525354.pdf
    • http://ourdesign.hk/ckfinder/userfiles/files/vizer.pdf
    • https://korzayithalat.com/spot/admin/fckeditor/userfiles/file/tobefewinorinezise.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/natf77mq4oe65ivdb6pfmscaf7/68822439521.pdf
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/sowobetudes.pdf
    • http://www.azurwelcomeservices.com/userfiles/file/nopuzadujemizurowuzix.pdf
    • http://marsalanoleggio.it/userfiles/files/45995272993.pdf
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/161402e86a9c73---sifuxipu.pdf
    • http://xn--h49al71atridzo.com/userData/board/file/38869564898.pdf
    • https://xrtradingfeedback.com/cmsimages/file/29908313712.pdf
    • http://9meclinic.com/ckfinder/userfiles/files/9536764292.pdf
    • http://candleelectricals.com/uploaded_files/userfiles/files/52645759027.pdf
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/dgia87n9b4hspogrjvke3n5ugc/salisajufozemo.pdf
    • http://juditphotography.com/picture/userfiles/file/jelometujejele.pdf
    • http://qdjshg.com/files/file/bolekabixogovekixoko.pdf
    • http://hefei.chinatupai.com/web/js/ckfinder/userfiles/files/kusexorofawate.pdf
    • https://gencerenerji.com/resimler/files/tiwuzulugige.pdf
    • http://valkexclusief.reviews/app/webroot/files/userfiles/files/viwuzizibita.pdf
    • https://sjamsul-hidajat.id/ck_uploads/uploads/files/rapedakov.pdf
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133d8ddf0d12---xoxetupotigine.pdf
    • https://jin-hung.com/userfiles/file/fiwepa.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=need+notification+access+permission
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cbb2.bin
d150d0f70c7637737d9984ba13505dd03ba24324986cc8aee9da8f93cc62d2ed
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBB2 10712 bytes
font_01_sfnt_off0000e44e.bin
99c616cd07dfbdb70eb78e1ef66d7d45cd75496073b833a837f624cb30daf860
pdf-font-stream PDF embedded font (sfnt) at offset 0xE44E 17568 bytes
font_02_sfnt_off000111a0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x111A0 16792 bytes