Malicious PDF — malware analysis report

Static analysis result for SHA-256 23e8d9f764ceb011…

MALICIOUS

PDF

83.2 KB Created: 2021-09-19 11:49:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: dab4dab7d534274834f6a1388140c4e1 SHA-1: 560e91ee8beb3cb945c1215a116cc5c8538a7502 SHA-256: 23e8d9f764ceb0110ef0c0f010033cb45a31f4b5aff22db755564bd3d0ba696f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and numerous external URIs, many of which are part of a link farm hosted on compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious sites, which are designed to deceive users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://huntic.ru/uplcv?utm_term=tcp+optimizer+android+apk PDF link annotation
    • http://www.anaja-inter.org/public/file/tulikomiwabigewuvewewizig.pdfIn PDF document text
    • http://wenyanchem.com/upload/files/zedizezuworixoka.pdfIn PDF document text
    • https://sporyolu.com/resimler/files/fifumupakepulon.pdfIn PDF document text
    • https://cokhivietuc.com/img-vietuc/files/fokixusogisokiw.pdfIn PDF document text
    • http://refpecsbelvaros.hu/kepek/files/3967803947.pdfIn PDF document text
    • https://lotteppta.com/beta/assets/file/pakosozawoxoninurolewi.pdfIn PDF document text
    • https://www.santaterezinha.com.br/js/ckfinder/userfiles/files/demekuruvinabobew.pdfIn PDF document text
    • https://snoman.mb.ca/ckfinder/userfiles/files/wuwalikupopajixaj.pdfIn PDF document text
    • http://saatgaamkansarasamaj.com/admin/uploads/files/9847726041.pdfIn PDF document text
    • http://2015.letnifestiwal.pl/ckfinder/userfiles/files/59458093688.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/im04pfo8pkajcp2cva32in5pi3/13596765465.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1613ddeab97bc0---wuribatageruzunefazodazo.pdfIn PDF document text
    • http://crimesla.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/foborupew.pdfIn PDF document text
    • http://candientushinko.com/images/file/29098858732.pdfIn PDF document text
    • http://robvancampen.nl/userfiles/file/lakemedu.pdfIn PDF document text
    • https://creativenursery.net/home/creative/public_html/ckfinder/userfiles/files/dorudiwik.pdfIn PDF document text
    • http://tipsclubcr.com/campannas/file/5865000954.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/16144358b4711e---76899367072.pdfIn PDF document text
    • http://av72-reklama.ru/userfiles/file/1631789275ad196a5085f5ed91e58d.pdfIn PDF document text
    • http://www.prctech-th.com/ckfinder/userfiles/files/sekemikovi.pdfIn PDF document text
    • https://hostsolutions.ro/app/webroot/files/userfiles/files/lotuvanimufigiguzo.pdfIn PDF document text
    • http://signauction.net/userfiles/file/3830653260.pdfIn PDF document text
    • https://ecpa.fr/uploaded/file/kuritobom.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/0e1a7b08dde1eb9ce39d0406adb9b552/30824822857.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_off0000df8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF8A 10576 bytes
SHA-256: 3899b00cadb88f0f72b5bda81fdb8b48f2e9fad8a8ad5ca26cd0d6399f5a4532
font_01_sfnt_off0000f7ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7AD 17716 bytes
SHA-256: 582bebd8f3083be72e51c5077c947eeea950c2adb92b4e4421a996ebed2ef5c6
font_02_sfnt_off00012615.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12615 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1