Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef905ee30556ec65…

MALICIOUS

PDF

132.0 KB Created: 2021-09-08 00:00:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 37e06f266f75a1870c7c0a36fffd426b SHA-1: dfe04a582ebe25e419bef694b3f13dcda9fa9cab SHA-256: ef905ee30556ec65149cd49488162ce080aaa270ea0d6c362231beb607666560
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, but the PDF structure itself is the attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb1ea3602e---68053530399.pdf In PDF document text
    • http://lifeisartfoundation.org/sites/default/files/images/userfiles/file/gokumavifesaxoguruka.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bc044c6b4e---21148649188.pdfIn PDF document text
    • http://www.alborada.es/ckfinder/userfiles/files/98454332040.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ae2fa246d5---vuxiwasaloxojulijelano.pdfIn PDF document text
    • http://jyjjapan.jp/files/ckeditor/files/30872253463.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1606d1879b9624---mivadi.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160942d3d1fbe0---78874128909.pdfIn PDF document text
    • https://ksuskalology.com/images/file/dotovaler.pdfIn PDF document text
    • https://equator-maritime.com/userfiles/file/fepoviko.pdfIn PDF document text
    • https://batikatravels.com/userfiles/file/sazudepoloposerexafumen.pdfIn PDF document text
    • http://dkmmotor.com/files/userfiles/file/kagagor.pdfIn PDF document text
    • https://psiakocky-potisk.cz/webpagebuilder/ckfinder/userfiles/files/diwaselane.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1611bac0495552---80024925395.pdfIn PDF document text
    • http://goreskyreunion.com/clients/b/ba/ba087d28c24afe6c5bc45fa062332e47/File/6902312026.pdfIn PDF document text
    • http://cz-synergy.cz/data/file/67885472446.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/cc1186c4514a45093e0906b112b8d23e/sibojalumidapefijezi.pdfIn PDF document text
    • https://upbilbao.com/ckfinder/userfiles/files/24795143935.pdfIn PDF document text
    • https://imagebeaute.fr/userfiles/file/lafixinolitositonexed.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/b3b97616c0829def5a1aa6bc78de3e8c/42137735933.pdfIn PDF document text
    • http://duancanhotot.com/upload/files/92946167783.pdfIn PDF document text
    • http://medica-eg.com/userfiles/file/5894474354.pdfIn PDF document text
    • http://coffee33.ru/archive/file/11364028278.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=fallacies+in+philosophy+pdfPDF 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_off00019115.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19115 24976 bytes
SHA-256: 761a606db390fc5ee73908fed5306869c407efba425cf2a5e44e992d710c8f60
font_01_sfnt_off0001d20e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D20E 10612 bytes
SHA-256: f7b5f6c202f5a4a5e7a226d3814530f79f3a70b6a7f819ef752d2b81462eb947
font_02_sfnt_off0001ea2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1EA2E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1