Malicious PDF — malware analysis report

Static analysis result for SHA-256 c936c1bc8705fec7…

MALICIOUS

PDF

88.4 KB Created: 2021-08-14 03:15:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d86986c0fdc5815691041cf6e7b4c6d4 SHA-1: f084262086c469b995c459c7e65aa414555c440c SHA-256: c936c1bc8705fec70adc86cd2be12391aee308bf7d16d239ab17cf47ec837eed
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous URLs pointing to potentially compromised websites or disposable hosting, suggesting a phishing or malware distribution scheme. The PDF structure and embedded links are indicative of a link farm used to redirect users to malicious sites, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://snqrsl.quebec/upload/editor/file/32861369382.pdf In PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1606c909bc6e65---koruvunenaru.pdfIn PDF document text
    • http://wrtour.com/FileData/ckfinder/files/20210605_2C5C86ECA1930ED4.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c53f305e3cd---22873138175.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/ad2d356ca141f399b111c4ce68a66ba7/bowuragaxelavagoriw.pdfIn PDF document text
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/7e90vjc3mdkilp3gcn2krvv8qi/pebekakaferuxuvom.pdfIn PDF document text
    • http://elma-itc.ru/!upload/files/43960076143.pdfIn PDF document text
    • https://combrooncom.com/contents//files/63847761517.pdfIn PDF document text
    • https://gerastar.com/userfiles/file/sewenekotobo.pdfIn PDF document text
    • https://norservis.cz/files/files/98903349609.pdfIn PDF document text
    • http://x-site.by/upload/editor/files/19581919743.pdfIn PDF document text
    • https://montpellier-business-plan.com/mbp/upload/images/images/upload/ckfinder/nixesawoviru.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/i959oh8js3vi5n8a6nqrmd1on0/40042446000.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160779a6a074e9---mipedatubobazibeleme.pdfIn PDF document text
    • http://parfumerieindex.nl/images/uploads/kavipig.pdfIn PDF document text
    • http://nt-module.ru/ckfinder/userfiles/files/63313525282.pdfIn PDF document text
    • https://www.dartmusicfestival.co.uk/wp-content/plugins/super-forms/uploads/php/files/334ca60a6869f4c4c15e498e454648ec/gixipa.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/1f387abf5c94a7f8669e8e53a9de6de1/fenojuxixizaxugotuxabovu.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/48046609532.pdfIn PDF document text
    • http://thekitchendesignstudio.org/uploads/files/1446635328.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1c726570dc---19491269663.pdfIn PDF document text
    • https://balustrady-metalik.pl/files/20149087876.pdfIn PDF document text
    • http://www.associatedomains.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607579078d005---dofabuni.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160d8c91fdd5e5---82778482610.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608006299b3a3---ririjatijodapupezuru.pdfIn PDF document text
    • http://qkmedica.com/uploads/userfiles/file/nipiniwisetubu.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b31d2a32e4---molomabujo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=english+lesson+plan+format+for+primary+school+pdfPDF 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_off0000f5aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010dc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DC1 11164 bytes
SHA-256: 88ac766f45ceced33a468d2882263b7e80848ed02c361f1e4eda81d09ea61d24
font_02_sfnt_off00012774.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12774 16740 bytes
SHA-256: 82e6d475f3af097ece2ff567f49521abb943b87c4dcfae3dbe56d48188827d38