Malicious PDF — malware analysis report

Static analysis result for SHA-256 c53f76316f0f2252…

MALICIOUS

PDF

70.0 KB Created: 2021-09-26 00:21:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 95ac32f835ad54d8123fa3ea1656c2bc SHA-1: 82427a841b3362f191e5334f28c552bd9d7d4130 SHA-256: c53f76316f0f2252bcb2d801998189f5f21e630cf5cbebc590c287642d0e1f84
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous links, many of which point to compromised WordPress sites and disposable hosting, indicating a link farm designed to manipulate search results or direct users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • 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.
  • 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://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/d7e940dfdfed33b2abfc235f95f625c7/bifulije.pdf In PDF document text
    • http://cmrivestimenti.com/userfiles/files/32720265192.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/6pcab6ugf35vb4bd0qe7a38s73/gazumopivibiwobajo.pdfIn PDF document text
    • http://xn--80akoseq9f.xn--p1ai/userfiles/file/69205015470.pdfIn PDF document text
    • http://thsport.dk/ckfinder/userfiles/files/dimopolunoliva.pdfIn PDF document text
    • http://candybeauty.vn/upload/files/12957271881.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c1020a6809---91637180529.pdfIn PDF document text
    • http://nbnjl.com/userfiles/files/2274470647.pdfIn PDF document text
    • https://moderator.lt/components/com_mijoshop/opencart/image/data/files/sovawadutubunaseji.pdfIn PDF document text
    • http://ctmmaximoravenna.com/ckfinder/userfiles/files/nekafadukituj.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///pepuporanasulosaxavav.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/q1483e4admbsmn8r3mdabgo7e3/jojawosipi.pdfIn PDF document text
    • http://jj-metals.com/userfiles/file/2021090407141773499.pdfIn PDF document text
    • http://fazekaskozpont.hu/images/upload/file/12842544103.pdfIn PDF document text
    • http://nemochem.cn/upload/files/faxusiwidoxukikum.pdfIn PDF document text
    • http://smartpaintingplus.com/userfiles/files/99896333810.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1612fa70c1e440---3691562678.pdfIn PDF document text
    • https://loppisidjupdalen.se/images/uploaded/file/lovuvipesosamosuxizovet.pdfIn PDF document text
    • http://bladensburg.abwingsmd.com/uploads/files/nidiwatez.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/2c32e71a97f9a512776187fa65d82cd4/71005699946.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/161409259842a1---25496140892.pdfIn PDF document text
    • http://sevvalturizm.com/rsm/files/98549728008.pdfIn PDF document text
    • http://buyyoutubesubscribers.com/ci/userfiles/files/sigebegovopufojoru.pdfIn PDF document text
    • https://avukatwebsitesi.kocgrafik.net/upload/files/67480876713.pdfIn PDF document text
    • https://eletvital.hu/uploads/files/17964547174.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=best+paid+game+androidPDF 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_off0000b22c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB22C 15652 bytes
SHA-256: 7781e80bc6e4b7b7f4cb54a11773821e5a181ec835a46ba6b8ebf913c41739ac
font_01_sfnt_off0000d9e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f1fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1FB 10740 bytes
SHA-256: 730f336b7499950dc7e1365a49c579fd98e1d987a35d86f59b6196aa123df8e5