Malicious PDF — malware analysis report

Static analysis result for SHA-256 b02f8c8d4379c837…

MALICIOUS

PDF

75.9 KB Created: 2021-09-03 00:10:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8a3f56967954be888f5375443325df8e SHA-1: 447a3cb85ab427def9f6b381b3b0b707c88f2493 SHA-256: b02f8c8d4379c837376059f0fbc750b44020404e65754717f79dc7cb912bd020
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as link farms. ClamAV detected this file as 'Pdf.Phishing.Trojan', and an ML classifier also flagged it as malicious. The primary function appears to be redirecting users through a series of links, likely to a phishing page or a site hosting a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/fbbad20400008c720c09966bb53e6613/79049457827.pdf In PDF document text
    • http://steelfurniturecn.com/d/files/9925381792.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/63uvomig9i2otai5nsffftnsjg/98623216636.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/tenigalipafepof.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/ccf16ksp471flor56u3strg2m3/2964282698.pdfIn PDF document text
    • https://celebicatering.com/upload/ckfinder/files/tojuvunaxiwutiwujarewo.pdfIn PDF document text
    • http://jnmindia.com/outscapes/admin/ckeditor/uploads/ck/files/36618361081.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a33c588c9bb---viwogapexunol.pdfIn PDF document text
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/3f718d90f53ba5294efc3cfad6a3dd0e/53975884240.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/ilomia29i2bqu9qdnfekn5jmgp/59331427782.pdfIn PDF document text
    • http://ekolojikweb.net/upld/userfiles/file/18102253896.pdfIn PDF document text
    • https://thietbidienmanhcuong.com/upload/files/38867502130.pdfIn PDF document text
    • https://nestsearch.in/admin/uploads/file/vopigidaw.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607a7e8eb7d7c---16558592067.pdfIn PDF document text
    • https://cicasoftavukatwebsitesi.demowebsiteleri.com/upload/files/17979899998.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/c4c85c51f11f206be6525aacda38e325/lemijipikojaniravu.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/vsqhrn6frlgesh45p5pktvaft4/nolupukimolotevebiwabu.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077d98f6017c---62901945313.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1c0851ed92---lifamexunegejakid.pdfIn PDF document text
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/04a284f5bfaf0ea76d150bd366935b49/rilopesulirorinobivuvupo.pdfIn PDF document text
    • https://asharfilalkulfi.com/ckfinder/userfiles/files/10509812724.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/judubopekibodulajav.pdfIn PDF document text
    • http://commsoft.nu/demo/ktb/wsmbilder/files/nitovabe.pdfIn PDF document text
    • http://lagunaapartman.hu/images/user/file/87693346677.pdfIn PDF document text
    • http://netcentricnj.com/ckfinder/userfiles/files/60454118475.pdfIn PDF document text
    • http://bukharageorgia.com/sites/default/files/file/33424743669.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=vitamin+k2+and+the+calcium+paradox+pdf+downloadPDF 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_off0000c4ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD11 16584 bytes
SHA-256: 1531f05aa69f28747286c9a5f8f63ad6aad747abd88c979e8612f7173d517d75
font_02_sfnt_off000107ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107AD 11188 bytes
SHA-256: 5fd0bd418fa49c6ad5e31e7277b8d83a71f74c649af8c4d246000b390ebf6286