Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec08335427cc7390…

MALICIOUS

PDF

83.6 KB Created: 2021-09-18 03:11:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 1454581947abe149e09c7be7d603d4eb SHA-1: 27252e355dddb5686aa52496d2337d1696ece771 SHA-256: ec08335427cc7390f4a9e82155dbed6a3abaadb99241bb0b68e84a461afda930
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS upload directories or are part of a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or redirecting users to malicious sites. The embedded JavaScript is a common technique for initiating further malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://synerhu.ru/uplcv?utm_term=the+inner+game+of+tennis+by+timothy+gallwey+pdf PDF link annotation
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/345e48fe1784c5a9c907b33c21eaa7e8/49856717413.pdfIn PDF document text
    • http://www.ruben.pl/ckfinder/userfiles/files/64243938527.pdfIn PDF document text
    • http://vzwsportenmuziek.com/content_docs/gelix.pdfIn PDF document text
    • https://printsolutions.printsolutions.bg/uploads/wysiwyg/files/repiragikaxisenumolij.pdfIn PDF document text
    • https://newsale.linyn.mobi/upload/ckeditor/pages/files/84349229872.pdfIn PDF document text
    • http://lutechmed.com/Images_upload/files/14707794571.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fcf4ca7fde---78148298647.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/6a605f46d7fd5e541e033c909680b72c/jinonawakogilun.pdfIn PDF document text
    • http://dulwichtaxi.com/survey/userfiles/files/nikafepezodipilaxonarule.pdfIn PDF document text
    • http://cnmrobotics.com/files/files/33423595582.pdfIn PDF document text
    • https://avflash.nl/upload/files/xironetekoxaliredeku.pdfIn PDF document text
    • https://padservhosting.com/userfiles/file/72834806794.pdfIn PDF document text
    • http://yetisirkaucuk.com/firma/files/jikakasizovijalujet.pdfIn PDF document text
    • http://unicorn-furnitures.com/d/files/kagamubik.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/gigutorinedazusuvubakaf.pdfIn PDF document text
    • http://www.catedralirodahaz.hu/data/editorfile/xekovuwakoka.pdfIn PDF document text
    • http://fibertechnique.com/tmp/file/27423534444.pdfIn PDF document text
    • https://konzolstudio.ro/uploaded_files/file/lovam.pdfIn PDF document text
    • https://jokerprod.net/userfiles/file/36286377198.pdfIn PDF document text
    • http://cpbnatation.fr/fckeditor/userfiles/file/68496331152.pdfIn PDF document text
    • http://topflexsports.com/uploads/50889187574.pdfIn PDF document text
    • http://tksvolga.ru/userfiles/file/8376548593.pdfIn PDF document text
    • https://avukatwebsitesi.trakyasoft.com/upload/files/97860642760.pdfIn PDF document text
    • http://katyababash.com/images/uploads/file/2022586492.pdfIn PDF document text
    • http://longbienco.com/js/ckfinder/userfiles/files/bapegoduzatelelonu.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_off0000df9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF9B 18068 bytes
SHA-256: 7078e9752d1fa8b71925b22e4ff92ca4a0d7f76b3199b8ea98c959438789313e
font_01_sfnt_off00010e21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E21 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012638.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12638 11248 bytes
SHA-256: 289bb7f99929d7506cfc7a4bc33ea50a0951532bb6021a342fd8da867c3c1a06