Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac1fa5c6c6416b58…

MALICIOUS

PDF

71.1 KB Created: 2021-10-01 03:06:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 695a33d7127cac400eff1a4b3b1b27f9 SHA-1: ae3b44013fe0af5c82596e9f59e62e37237cd40f SHA-256: ac1fa5c6c6416b586f48ba7194bb40d6359868e840285f13018a328f60e05cb3
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the nature of the URLs and the PDF structure align with common phishing and malware distribution techniques.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://nomylo.ru/uplcv?utm_term=best+android+volume+booster+2020 PDF link annotation
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614a0f9f0bcb7---jawaf.pdfIn PDF document text
    • https://n-vv.dk/userfiles/file/5430209571.pdfIn PDF document text
    • https://www.rapn.ru/ckfinder/userfiles/files/37984039304.pdfIn PDF document text
    • https://jlgardner.org/home/jlg/public_html/ckfinder/userfiles/files/gowajaxigaxirilemedineja.pdfIn PDF document text
    • http://primebrokeragetx.com/ckfinder/userfiles/files/bezazosuviv.pdfIn PDF document text
    • http://mvsexpo.ru/admin/ckfinder/userfiles/files/91961005693.pdfIn PDF document text
    • https://mehreganimaging.com/images/upload/files/fuxuvununoziwiwewigil.pdfIn PDF document text
    • http://customize.fr/fckeditor/editor/filemanager/connectors/php/img/Editor/file/tobakakisixekidubusa.pdfIn PDF document text
    • http://kerrya.com/ckfinder/userfiles/files/71427813950.pdfIn PDF document text
    • https://www.psk.com.au/application/third_party/ckfinder/userfiles/files/89860585839.pdfIn PDF document text
    • https://foodphotoshop.com/userfiles/files/44323384359.pdfIn PDF document text
    • https://horgaszvelem.elelmiszer-hazhozszallitas.hu/ckfinder/userfiles/files/95188409226.pdfIn PDF document text
    • http://dachastyle.com/userfiles/file/50383440882.pdfIn PDF document text
    • http://jump360.co/upload/files/20210902040011.pdfIn PDF document text
    • http://ecogestval.es/userfiles/file/47794721515.pdfIn PDF document text
    • https://gianlucabruno.it/dati/upload/file/zenirewurugixubapixerex.pdfIn PDF document text
    • http://c-amc.com/upload/files/vafasaxenop.pdfIn PDF document text
    • https://vietnaminsight.biz/ckfinder/userfiles/files/5853755361.pdfIn PDF document text
    • http://proxkimya.com/resimler/files/60413665260.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d961703461---sesajid.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/303911e36936631ed4b2b3d55e4c08a1/jogag.pdfIn PDF document text
    • https://bharatceramics.in/ckfinder/userfiles/files/genexebexukusum.pdfIn PDF document text
    • http://kamakuralosgatos.com/uploads/files/87074653187.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_off0000b0a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0A6 17364 bytes
SHA-256: 7fc0a37bda6da0a541455790700206663a52cfd6c78882d1a0fcfc543b2a5049
font_01_sfnt_off0000dd4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD4F 11008 bytes
SHA-256: 3c2c4e14b87d8e69fb95bc4a3dfa4eca09ea43e0bbe3d211a5c20018a688403c
font_02_sfnt_off0000f6f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1