Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b4dba14e7fbc87a…

MALICIOUS

PDF

81.5 KB Created: 2021-09-09 06:05:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ff8b58a887d6ae06dddf2a52b8cbf88c SHA-1: 27ceab4b7f81ebe806ba1c37d8a2464efb2aa81f SHA-256: 3b4dba14e7fbc87a1d3c8fa0a8e17026cb74cdf3e6853e10d083d09df21d34d1
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier with high confidence. It contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, suggesting the document's purpose is to host a collection of links for malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://irlanc.ru/uplcv?utm_term=apk+editor+pro+2020 PDF link annotation
    • http://duda-tech.pl/dudatech/upload/file/95944865578.pdfIn PDF document text
    • https://ichapps.com/ichapps/ckeditor-ckfinder-integration/uploads/files/90999918913.pdfIn PDF document text
    • http://zkojicin.cz/userfiles/file/gimovubavo.pdfIn PDF document text
    • http://worshipedia.mobi/sites/default/files/file/5199882264.pdfIn PDF document text
    • https://biserica-izvorul-tamaduirii.ro/files/42561901854.pdfIn PDF document text
    • http://muzycznescyzoryki.pl/userfiles/file/76804657007.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613932df10b50---bupolaboja.pdfIn PDF document text
    • http://cobansut.com/userfiles/file/guzazuxukodatateji.pdfIn PDF document text
    • http://theonejsc.com/userfiles/file/najokarozuxafozaxefu.pdfIn PDF document text
    • http://thailaundry.com/imgUpload/files/viwojazujuzoke.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/ccedad587f95a5007eab8649ee851d6e/49035530980.pdfIn PDF document text
    • http://seasonsblinds.com/uploads/ckfinder/userfiles/files/safekixexupuxez.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130ed916b047---52220278104.pdfIn PDF document text
    • https://szpital-sulecin.pl/images/fckfiles/file/wulefewiwogiwi.pdfIn PDF document text
    • http://baheth24cars.com/ckfinder/userfiles/files/43780224648.pdfIn PDF document text
    • https://globalcircle.club/userfiles/file/4097026873.pdfIn PDF document text
    • https://toocapen.com/files/bevijoxixe.pdfIn PDF document text
    • https://sydneystudytour.com/accounting/userfiles/file/10152278078.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16135b19ee5f30---63491918521.pdfIn PDF document text
    • http://hide-bo.com/img/tmp/file/25338807647.pdfIn PDF document text
    • http://polletnv.be/uploads/files/fevajarek.pdfIn PDF document text
    • https://masukpt2.com/contents/files/29695859446.pdfIn PDF document text
    • https://klcconsulting.eu/klc/file/83814033707.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_off0000d2b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2B7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eace.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEACE 10220 bytes
SHA-256: 29aa08ea795391a97aa4feb069d98b055a1383256c6f6cee293ad208aab72853
font_02_sfnt_off000101e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101E0 20412 bytes
SHA-256: 1c6438b823880e1c245f8d7ad82a11626b77bd3298b1e308713460f2d48c31cc