Malicious PDF — malware analysis report

Static analysis result for SHA-256 0b8787edb53c3c50…

MALICIOUS

PDF

79.1 KB Created: 2021-09-15 16:38:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 702d9b23967cbabf4ba0bad1d048b4f7 SHA-1: 5f322bc6074946f4176a3f991fdda92a8ee40f23 SHA-256: 0b8787edb53c3c50bb9eff0e2ff584b61d6710a45503a501474bb5f5d2620751
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery via these external links.

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://coretry.ru/uplcv?utm_term=anatomical+regions+of+human+stomach PDF link annotation
    • http://dubilex.com/userfiles/files/tipifovelebi.pdfIn PDF document text
    • http://ildongwire.com/userfiles/file/livojulijukutaxo.pdfIn PDF document text
    • https://hotelreviewreserve.com/basefile/hotelreviewreservecom/files/jubadatebalemijokukigova.pdfIn PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/32213649378.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e04adc13a9---42272641061.pdfIn PDF document text
    • http://kanalizace-ul.cz/userfiles/file/beres.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139b4bf2409c---84527688865.pdfIn PDF document text
    • http://superfasttv.com/uploads/files/47276156610.pdfIn PDF document text
    • http://naturallabs.de/userfiles/file/foxawexolo.pdfIn PDF document text
    • http://darstin.com/userfiles/files/xututiwar.pdfIn PDF document text
    • https://kemxoi.vn/app/webroot/files/images/pages/files/lajofetepi.pdfIn PDF document text
    • http://sb-78.ru/files/file/89589392517.pdfIn PDF document text
    • https://koncnc.com/genelresimler/file/dugutonadebiwimobesuxo.pdfIn PDF document text
    • https://ekinyalitim.com/depo/sayfaresim/file/nesesakuxa.pdfIn PDF document text
    • http://audidalys.lt/ckfinder/userfiles/files/95968471211.pdfIn PDF document text
    • http://ozt.zielonetarasy-cieplice.pl/uploads/userfiles/files/43358474550.pdfIn PDF document text
    • http://lafiestadelmoto.cz/files/file/rovusonisojawufekodukomoz.pdfIn PDF document text
    • http://dentherapia.hu/files/file/ruvosezovusitemo.pdfIn PDF document text
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/a1fddad95452a157cb98bda570965130/86566092043.pdfIn PDF document text
    • https://digireg.lu/upload/12639223033.pdfIn PDF document text
    • http://borisovhlebprom.by/var/upload/file/sikaru.pdfIn PDF document text
    • http://dailythang.com/userfiles/files/ruravaxovavado.pdfIn PDF document text
    • http://cableesmaltado.com/d/files/zazumobiwajexutamovijo.pdfIn PDF document text
    • http://hyunsin.net/userfiles/file/8577884373.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_off0000cf87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF87 17908 bytes
SHA-256: ffe9c4438ce719846d5446f729c830613c7ff2abdd4a4483103414fc1598e0d0
font_01_sfnt_off0000fdda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000115f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115F1 10864 bytes
SHA-256: 3d863b0e19aa3dd569a215d3f9fade5b956e27ea6c56040f0d58a5648ef6b935