Malicious PDF — malware analysis report

Static analysis result for SHA-256 37500b84bba84f47…

MALICIOUS

PDF

76.0 KB Created: 2021-09-10 20:20:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e23b79071abda30822e38072c8958bfa SHA-1: f41c9939ed5bf778c1afaed6e43504b0c2df3549 SHA-256: 37500b84bba84f4757ff09802b45731104fe4fad1f2d67f1167cdae1290b509f
164 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 embedded JavaScript and a significant number of external URIs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The primary function appears to be delivering users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pixomot.ru/uplcv?utm_term=assassins+creed+hd+apk PDF link annotation
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161391507df5dd---mowojavute.pdfIn PDF document text
    • http://wittymall.com/multimedia/userfiles/file/95073619798.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb3b18db5f---97198514348.pdfIn PDF document text
    • http://china-miyaco.com/img/file/2021939222.pdfIn PDF document text
    • http://tokyoto.pl/UserFiles/file/kevenotinefulenexuxop.pdfIn PDF document text
    • https://ifbscalidad.eus/files/galeria/files/kitaj.pdfIn PDF document text
    • http://www.vnos.vn/app/webroot/uploads/files/1334926249.pdfIn PDF document text
    • http://mos-craciun-inchiriere.ro/fckfiles/file/18247505294.pdfIn PDF document text
    • http://xutricolor.com/uploadfile/files/71971082888.pdfIn PDF document text
    • http://lagostena.it/userfiles/files/momub.pdfIn PDF document text
    • http://autovoda.ru/upload/files/9447634229.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/c3980e3bf2f151ccfb370d35a2e9f9dd/16562334321.pdfIn PDF document text
    • https://www.ijmsir.com/ckfinder/userfiles/files/21332418942.pdfIn PDF document text
    • http://www.portaldasfreguesias.com/portugal/vianadocastelo/vianadocastelo/geraz_do_lima_sta_maria/ckeditor/ckfinder/file/sumiruvekujupuzox.pdfIn PDF document text
    • https://okinawa4d.com/contents/files/22294180118.pdfIn PDF document text
    • http://friend5190.xyz/js/ckfinder/userfiles/files/sodev.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/ca172199db4822dbb46e03d9e2b65f7a/70080028573.pdfIn PDF document text
    • http://idrogastermoclima.it/Utentifile/FCKPage/file/rezinetolajenatozakoxagi.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/75246232572.pdfIn PDF document text
    • http://machinesupplier.cn/data/product/file/202194_154746_888.pdfIn PDF document text
    • https://telliogluhukuk.com/userfiles/file/66480104051.pdfIn PDF document text
    • http://www.dgtrans.co.th/login/ckfinder/userfiles/files/38875010961.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_off0000c2b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2B7 18424 bytes
SHA-256: ca939821c4e2e9766597af2f1e628f54eb2bc4eb1031541795acdb401c47e182
font_01_sfnt_off0000f2ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ae1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AE1 10420 bytes
SHA-256: 76e9bb3ccb8b47a9374f8f9e65a6562a3bd3265c10642812982d03f04d48b50e