Malicious PDF — malware analysis report

Static analysis result for SHA-256 d83985e5dfd4a286…

MALICIOUS

PDF

68.2 KB Created: 2021-09-16 15:53:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d849681db6208bd322daf136b7415974 SHA-1: 803dc6e5ae95f1d9bf5d4913439453b5face4989 SHA-256: d83985e5dfd4a2864484d7ae3ab3e2d946ff7c0188648b88dea6cb079e0378bd
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document is identified as malicious by ClamAV and an ML classifier. It employs a common phishing lure technique, presenting itself as an image-only document to conceal clickable links. The embedded JavaScript and numerous external URIs, many pointing to compromised CMS uploads or disposable hosting, suggest an attempt to redirect users to malicious sites for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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 http://usa-ex.com/images/blog/file/82281917271.pdf
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/fv6iiohjvjivrce41vkejlcr52/55382154184.pdf
    • https://sreekanakananda.com/ckfinder/userfiles/files/fikeramuwipinivaxomu.pdf
    • http://ingenermarket.ru/userfiles/mukabaxinoxem.pdf
    • https://shindah.com/images/ckeditor_img/files/wuwaduzodeve.pdf
    • http://klawiatury-foliowe.pl/_data/file/zegef.pdf
    • http://5thaveseniors.org/userfiles/file/72887023319.pdf
    • http://ehoron21.mn/uploads/files/30511744547.pdf
    • http://www.cddfct.com/up_files/file/11669655887.pdf
    • http://www.szphotar.com/admin/img/files/jutibumofa.pdf
    • http://studiomuraca.eu/userfiles/files/zaferoniponotuxoxorilajit.pdf
    • https://santaclara.com/wysiwygfiles/file/dakogameduboj.pdf
    • https://ilonew.tasksplan.com/userfiles/files/dekukubiwarowojup.pdf
    • https://haciendaloscipreses.cl/upload/file/31665766114.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139c0c6bab18---zokan.pdf
    • http://marchmont.ru/imgs/file/nalifevowuduxiravepori.pdf
    • http://yuanjen.com/ckfinder/userfiles/files/65404339682.pdf
    • http://hanstime.com/userData/board/file/zilogorumasibubutetexuke.pdf
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/bb0aba21ebabf6d01f6bbcf6f821349a/konomiw.pdf
    • http://hfnhsw.com/upload/files/31592941301.pdf
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613841dab525a---buzuxodimokapojenunufu.pdf
    • http://sun-marche.com/app/webroot/js/ckfinder/userfiles/files/46549189516.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=4+letter+words+starting+with+ab
    • 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_off0000b0a2.bin
879813fadcde2f39569384252c3b347009b6373bdd77c5c29bc665541697e189
pdf-font-stream PDF embedded font (sfnt) at offset 0xB0A2 13884 bytes
font_01_sfnt_off0000d28d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD28D 16792 bytes
font_02_sfnt_off0000eaa4.bin
3c2d029bd7d8316982a3952a3fd1cc2621a97d13597bfd01dd90e7b8fc2be57d
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAA4 10732 bytes