Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d091da0759e0695…

MALICIOUS

PDF

69.2 KB Created: 2021-09-18 18:38:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4449c544b1f22df935df79f43bce8491 SHA-1: b7afc91ad5f3f48028ddd1993a88d9e21ac6baea SHA-256: 4d091da0759e06952aad6a469cd51238fd882886f51e4bbb7d401656a8712ba1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs pointing to various domains, many of which are associated with link farms and compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://laborke.ru/uplcv?utm_term=how+to+save+email+as+pdf+on+mac PDF link annotation
    • http://cuacuonanbinh.com/userfiles/file/4019731941.pdfIn PDF document text
    • https://nitm.ac.in/nitmeghalaya/ckfinder/userfiles/files/kevuzi.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613864e807eda---dukiviseresedijepenak.pdfIn PDF document text
    • https://growyourmoney.in/userfiles/files/31102466060.pdfIn PDF document text
    • http://metamorfozyayincilik.com/userfiles/file/86926100503.pdfIn PDF document text
    • http://hoigolfbinhthuan.com/users/files/vagusovasaminodiz.pdfIn PDF document text
    • http://hanasushimenifee.com/uploads/files/fiwasatavilukevowutotup.pdfIn PDF document text
    • http://taxicityplus.ru/userfiles/file/3880350412.pdfIn PDF document text
    • https://breedlife.com/upload/files/84184534310.pdfIn PDF document text
    • http://serviphony.com/tinymce/jscripts/tiny_mce/plugins/phpimage/phpimage/upload/images/file/zuwibuwefogikopexowewane.pdfIn PDF document text
    • http://soyaksiesta3.com/userfiles/file/bulusodisobogubisutomir.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135d01556c62---wemixebosuxawomidip.pdfIn PDF document text
    • http://retailpark.bg/uploads/wysiwyg/files/50907677804.pdfIn PDF document text
    • http://jualumnitoronto.com/editor/uploadfiles/79271874139.pdfIn PDF document text
    • http://mikllc.mn/uploads/files/61381018947.pdfIn PDF document text
    • https://brune-schmuckwerk.de/ckfinder/userfiles/files/56801596406.pdfIn PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/cc4d616d611cdb3b313235c0e0cdd85d/furisekasakufodesinosez.pdfIn PDF document text
    • http://flirtproducties.nl/ckfinder/userfiles/files/92421217898.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613b08e78c4ca---nojek.pdfIn PDF document text
    • https://longhungphat.org/Images_upload/files/rizitanara.pdfIn PDF document text
    • http://khyljg.com/uploadfiles/files/turogiselarukoxi.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_off0000b050.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB050 10824 bytes
SHA-256: e62345f9975fccb16c85a4a1bf325aa7594e5c2a6f47ff602751bdc3a39eb82c
font_01_sfnt_off0000c947.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC947 15180 bytes
SHA-256: 21d7abc85f6a8f514e9bacb47f90004d4d599ee04f49c9d7d9acc76644424717
font_02_sfnt_off0000ef8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1