Malicious PDF — malware analysis report

Static analysis result for SHA-256 140a09ba3d05cb98…

MALICIOUS

PDF

75.4 KB Created: 2021-08-29 11:19:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a5c8d52345494d8bb75c0b5541dc0cfc SHA-1: ee3b8c61ca5f661a6386a2a6aab08312b2626bae SHA-256: 140a09ba3d05cb985dabe485f1859489c61f3ed9de164d0d20cc6ad8fec18e0c
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 WordPress sites and disposable domains, indicating a link farm designed to lure victims. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The file's structure and numerous external links align with common tactics for initial access via malicious documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://crysiq.ru/uplcv?utm_term=how+long+should+the+mpi+be+retained PDF link annotation
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/o1ip7pltlnghklc8j2o7650rl6/tutobotunamuzeg.pdfIn PDF document text
    • http://jlm-kg.com/uploads/file/25639256233.pdfIn PDF document text
    • http://billagelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/doxap.pdfIn PDF document text
    • https://kfmaccounting.com/webroot/img/content/files/30768343186.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/57985888200.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/ca94dc5897fc97f886f999379ac26637/zanukubezumodusapev.pdfIn PDF document text
    • https://fuoriscena.eu/file/nozegizilovebidifopumusip.pdfIn PDF document text
    • https://himalmanpower.com/ckfinder/userfiles/files/669112508.pdfIn PDF document text
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/i8v28lh1m285deu647u4694rrq/17681480047.pdfIn PDF document text
    • http://www.drivingschool-brno.cz/files/files/dafarigunewonowoxup.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/fkehsfptl0j1m934afbkl351pj/70556647263.pdfIn PDF document text
    • https://pakianco.ir/data/image/uploads/news/files/56076453703.pdfIn PDF document text
    • http://zeguvietnam.com/uploads/ckfinder/files/tojixes.pdfIn PDF document text
    • http://pampa.be/uploads/userfiles/files/wamirikifafa.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/wasiwelegawumurinivikej.pdfIn PDF document text
    • https://www.spitalmoldovanoua.ro/ckfinder/userfiles/files/28657017563.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/a64l3iti1tsqcihr3p78hn8v9o/974369466.pdfIn PDF document text
    • http://nabisori.com/userfiles/file/30155769728.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160afc3c347c6b---9410854862.pdfIn PDF document text
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/c968e25489b59250ff18be11f70d3be6/raganug.pdfIn PDF document text
    • https://mamadona.ru/ckfinder/userfiles/files/ripator.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d88506901ff---20619385193.pdfIn PDF document text
    • http://impex-italia.it/userfiles/files/rotinodaneluvubaliziw.pdfIn PDF document text
    • http://yonseri.org/userfiles/files/sepiti.pdfIn PDF document text
    • http://beerskiboot.com/img/upload/file/17926188823.pdfIn PDF document text
    • http://perfekttorun.pl/pliki/36139680720.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_off0000c3f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3F1 11156 bytes
SHA-256: 99c3f76e9b84668347059eda9d8ab388e3e67130c5ab9562dba0480a6e7a8c42
font_01_sfnt_off0000dd5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD5F 16136 bytes
SHA-256: 09be0ec577308a420164db64d475e887fd973625e1f98d5802d6ca1dcceab81c
font_02_sfnt_off000106cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106CF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1