Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf85d9066c3ee9bb…

MALICIOUS

PDF

71.9 KB Created: 2021-09-30 19:12:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 18c5c50ad9f128deb844f26e5057fb14 SHA-1: 3f93b95cdeb302153b1aa3b88a689489cfc1d382 SHA-256: bf85d9066c3ee9bb6eafa03f8b57b48e714a768289c632937c589ae4cdd2078d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to manipulate search engine results or lure users to malicious sites. ClamAV detected this as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The presence of multiple link farm heuristics and the ClamAV detection strongly suggest a malicious intent, likely related to phishing or SEO abuse.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://luckysim.com/userfiles/file/17073966637.pdf In PDF document text
    • http://cnzhongkui.com/fckeditor/editor/filemanager/connectors/php/uploads/file/301007317744.pdfIn PDF document text
    • https://produktybhp.pl/pliki_user/File/butigofufutatuni.pdfIn PDF document text
    • https://kominove-centrum.cz/media/files/file/pafaselanumoxufebas.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/rosetavedenozob.pdfIn PDF document text
    • http://artvideo74.ru/upfiles/files/jutakevalupovi.pdfIn PDF document text
    • https://hbfilm.ca/resimler/files/21310382984.pdfIn PDF document text
    • http://debandhelder.nl/ckfinder/userfiles/files/sevupavubiluvolijikalefe.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130498315718---dawegawika.pdfIn PDF document text
    • http://farmina.ru/uploads/files/tawomenawubefimukub.pdfIn PDF document text
    • http://medizator.ru/ckfinder/userfiles/files/60180644987.pdfIn PDF document text
    • http://dryoucosmeceutical.com/userfiles/files/welixuto.pdfIn PDF document text
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/a3a2e7d16f30beb729d28527a333d167/1057954695.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132f7f5b011a---81876652050.pdfIn PDF document text
    • http://apvn.info/userfiles/file/kazivuvulugufujosilesute.pdfIn PDF document text
    • http://www.solarwindependence.com/ckfinder/userfiles/files/51909127847.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/161506143b02c3---najijedov.pdfIn PDF document text
    • https://armagedonspedycja.pl/files/file/zamujumufogumurojamut.pdfIn PDF document text
    • http://sochi-riba.ru/ckfinder/userfiles/files/2679101610.pdfIn PDF document text
    • http://www.kigimex.com.vn/ckfinder/userfiles/files/56014803656.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/h8c4kbj4rehh28oo7ul7ncsoq4/25936787966.pdfIn PDF document text
    • http://dhleisure.com/ckupload/files/15618029027.pdfIn PDF document text
    • http://king-pro.com/userfiles/files/sukomidu.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/8b3abb7d607c266374274f9c478280f7/63517582606.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=kannada+typing+keyboard+appPDF 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_off0000b556.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB556 10692 bytes
SHA-256: d56d1cc6a346cd856dc17adc6ba8ad9b0564808842ad36e8e58267fc7e2ec287
font_01_sfnt_off0000cd7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD7C 17356 bytes
SHA-256: 8f13e842d933a7af55b58171033b1865a3f59d7336c1f2a55dd29dd456162c67
font_02_sfnt_off0000f9a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1