Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4530803d1f5ab27…

MALICIOUS

PDF

79.1 KB Created: 2021-09-17 01:54:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 99e4542d9ee02954462d5c9d08e4a790 SHA-1: 9c5c8c15e945a2856cfc26d36fb57755967cb675 SHA-256: c4530803d1f5ab274ec5f475e618653a25cec3eecbee90186d4833d5cadb62e5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised WordPress sites and disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URIs strongly suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://ketchas.ru/uplcv?utm_term=star+trek+fleet+command+mod+apk+android+1 PDF link annotation
    • http://www.ecvbrass.ch/user/web/file/remunelujovibafulid.pdfIn PDF document text
    • http://ajej.pretty-match.com/upload/files/92416049739.pdfIn PDF document text
    • https://www.wizzfizz.com.au/application/third_party/ckfinder/userfiles/files/bofepola.pdfIn PDF document text
    • http://zkmeiqi.com/admin/ckfinder/upfile/files/73455094250.pdfIn PDF document text
    • https://studioconcept-stand.com/fck_userfiles/file/bixeganatisamer.pdfIn PDF document text
    • http://travellerisland.com/files/tirudutugiruxerupenudimub.pdfIn PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/e91138d5a37d5d84bda9d1f3cf0830d7/8977373632.pdfIn PDF document text
    • http://degeninhotel.ru/admin/ckfinder/userfiles/files/22150798650.pdfIn PDF document text
    • https://ppkh.net/userfiles/file/21229116418.pdfIn PDF document text
    • http://btfa.tw/upload/files/98075336086.pdfIn PDF document text
    • https://777mto.org/contents/files/lejiwixevazejilugovebej.pdfIn PDF document text
    • https://newegys.egyseg.eu/ckfinder/userfiles/files/33184910413.pdfIn PDF document text
    • http://mebco.ru/images/file/kobazobow.pdfIn PDF document text
    • https://techielingo.com/fck_uploads/files/85815853392.pdfIn PDF document text
    • http://www.santabriganti.org/admin/ckfinder/userfiles/files/lifumoriwujanifabebubav.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e919d08036---guwutew.pdfIn PDF document text
    • http://nbkhjc.com/uploads/202109/file/210904130905705332u0k419sla0be.pdfIn PDF document text
    • http://giasuthanhdat.vn/Images_upload/files/52340702747.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7229b2d76---39837225042.pdfIn PDF document text
    • http://kasargod.net/uploads/file/80989663338.pdfIn PDF document text
    • http://qcfloor.com/userfiles/file/buzapalapudumar.pdfIn PDF document text
    • http://ronaldtan.nl/images/photo/sinetimelif.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/fa031537e0715ca4e6fcfae5a4134b1f/dosokaz.pdfIn PDF document text
    • http://prakseologia.eu/userfiles/file/vimunex.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_off0000cd76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD76 10832 bytes
SHA-256: ccf0acf5bb2b86e4ed5e231aaac4b055c5551efeb730afb89eb0528ef3178f2c
font_01_sfnt_off0000e676.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE676 17844 bytes
SHA-256: b0b26558d7d0100777a5a24bdcc1381f22ad27edf41f111f97ae24f39d3777c8
font_02_sfnt_off000114dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1