Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c7efa73128d9cb7…

MALICIOUS

PDF

90.1 KB Created: 2021-07-22 15:52:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f658546b16ce8b8045cb67d3d4f413ae SHA-1: 9a4fded7219c184a8acfcf7a823014e8f4838467 SHA-256: 4c7efa73128d9cb7c74507affa6317ed95fdb10342fafe33ce14a011dbf20701
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608541d3c834d---4265755665.pdf In PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/ee5cd2aec725f1fed3220831aa74e773/39549933376.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160a8acdec33fc---womedinejisudo.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/5e615dbc76b9d66f1cf1cf08e5887766/bezek.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/xiwawo.pdfIn PDF document text
    • https://essaidafm.com/uploads/FCK_files/file/jojenixotuzawetevofefi.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/36cftr85dh5id8uhka2mg5b9bj/gisoruxoneke.pdfIn PDF document text
    • http://gasnguyenanhst.com/js/ckfinder/userfiles/files/situbusizofo.pdfIn PDF document text
    • http://chnli.tw/CKEdit/upload/files/88173978353.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f406bea27f---91240883737.pdfIn PDF document text
    • http://allmedicus.com/userfiles/file/83259158105.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/999de4b57d06010638475e72346caf50/zugedetokojodegezawaxam.pdfIn PDF document text
    • http://ingpiazza.eu/userfiles/files/59405811501.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9832e6027---92532593696.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b49d7f8112b---wovefowadopetusuneteb.pdfIn PDF document text
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609d57ad71d36---nelawidelufolasujaxeb.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb5f4a7ff42---73742257830.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/96833624756.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/48b163dc247e15d932499244f1eb1730/xilizuki.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7ac943dda---94946789684.pdfIn PDF document text
    • http://imbirimbir.ru/files/74936677580.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d81628cd1c---zafulumavegodazivaremo.pdfIn PDF document text
    • http://psychoterapia-przemysl.net/img/userfiles/file/tazavevizajetar.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=pertaining+to+the+palm+of+the+handPDF 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_off0000fa92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA92 18160 bytes
SHA-256: 2269078aac14eb3fa32d6819d694969796f0af150050f29dfd422f7515f5e2be
font_01_sfnt_off0001293f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1293F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014156.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14156 10776 bytes
SHA-256: 664382e56e49d1128a28aada422d023ee3dc21a8faa62b5dc2668aa8909c66cf