Malicious PDF — malware analysis report

Static analysis result for SHA-256 c68f8e7148c38441…

MALICIOUS

PDF

83.0 KB Created: 2021-09-05 07:08:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: c55047e3c9fe84e2bdcc1048263d8288 SHA-1: 6ed8660ebfa63248a55813532a49dc60695e023c SHA-256: c68f8e7148c384410c6b3db0ae4014902cf5c35a789f6c51c102285b2d2ac056
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable domains, indicating a link farm designed to lure users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://synerhu.ru/uplcv?utm_term=resume+format+pdf+ms+word PDF link annotation
    • http://unseretochter.ch/images/file/5285280097.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/bee218b6e38c84ad14c4d341d5f57cab/jukidoweterajox.pdfIn PDF document text
    • http://bebelino.ru/userfiles/file/82651072098.pdfIn PDF document text
    • https://webmakler.org/userfiles/file/9985712276.pdfIn PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/9e18414c2345df23d7fbbee319981f46/35750031980.pdfIn PDF document text
    • http://stellar.ru/ckfinder/userfiles/files/4636599187.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607e67eabb597---dutonixupodu.pdfIn PDF document text
    • https://mygenius.ru/admin/ckfinder/userfiles/files/97924807762.pdfIn PDF document text
    • http://topflexsports.com/uploads/76483481484.pdfIn PDF document text
    • http://indyskischool.com/ckfinder/userfiles/files/lazedugidul.pdfIn PDF document text
    • http://racecross.com/upload/edito_fckeditor/file/43949805735.pdfIn PDF document text
    • http://gpszone.hu/upload/userfiles/file/2165191633.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/10daa36bafffca5dcbff9ba3c5d25d71/bajakejulovijomapajutug.pdfIn PDF document text
    • http://itkaufmann.com/images/fckimages/file/sajudodabupuwokomanipi.pdfIn PDF document text
    • http://ressourcengarten.de/azubi/userfiles/files/11687607479.pdfIn PDF document text
    • http://sistersaviopublicschool.com/userfiles/file/manajiva.pdfIn PDF document text
    • http://miwon.com.vn/app/webroot/uploads/files/nadasikar.pdfIn PDF document text
    • http://www.hangmandigital.com/files/file/69344039040.pdfIn PDF document text
    • http://alexanderkanevskyartgallery.com/clientMedia/file/milizobukufajujifepawoxa.pdfIn PDF document text
    • http://lotusburbank.com/uploads/files/tinopudajutusiziba.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/af5c681e0959d3989e47594d441e8643/74891901099.pdfIn PDF document text
    • http://le383.com/uploads/files/linozevanekaxipilinupozin.pdfIn PDF document text
    • http://abnicum.com/files/file/bulifapamijon.pdfIn PDF document text
    • http://mulroyenvironmental.ie/userfiles/file/50651458491.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/3217f3bc4f57dd136f5f53ac9fcd5239/82684752459.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_off0000e221.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE221 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fa38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA38 10648 bytes
SHA-256: 3265c9487ad3b7801af00485107e701d2f9988495e15daa358a7cb033e2868fc
font_02_sfnt_off000112b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112B9 16692 bytes
SHA-256: 04585defe3847a8038840f26c37b39f6dd2fd0acb40f5545ff9df4dcfa017144