Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b5ff6f1ef481422…

MALICIOUS

PDF

91.5 KB Created: 2021-07-20 04:50:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8a481f6e52487ab6c0271be5922f91cf SHA-1: 46b85cd3091a961afc1292ffb1fea91fb82c3777 SHA-256: 4b5ff6f1ef481422d76e7eb26ee407adbda99bcb3626480a82faf6fef72e3913
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/40991b31319c897d82e8925b0fd03b1c/jevegefisatisete.pdf
    • http://anhuizhkj.com/upload_fck/file/2021-6-24/20210624121753172897.pdf
    • http://clinicaveterinariaalbese.eu/userfiles/files/81338285566.pdf
    • https://floraplant.gr/FCKeditor/userimages/file/13382715861.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160e2fc8632c50---kuviworukaj.pdf
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1606f7b79567d7---wukokakixowukawepor.pdf
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/8ntk897utga5f52a4dd60ivgom/63283164426.pdf
    • https://cleartunemonitors.com/ckfinder/userfiles/files/62417805669.pdf
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087292681bda---23696861459.pdf
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160984a65f1e47---voxora.pdf
    • http://yuha.be/_files/file/zimepabudinirozi.pdf
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b811529a26e---xozomimosexis.pdf
    • http://myphamhelios.vn/luutru/files/28758118987.pdf
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160afa9c5251d1---judawuwudidabafenewuk.pdf
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16094d5d00d2a2---1341333195.pdf
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608ba16a7cd4f---jazuxali.pdf
    • http://chickenwild.com/upload/contents/images/images/gavokuvizakukezizikipi.pdf
    • https://xn--80aaa1arbfjoe3bzh.xn--p1ai/data/files/betubokifon.pdf
    • https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/d12f9447841daca7dbd255b105fecf25/zezozalunigevijorisojiki.pdf
    • http://verduciautodemolizioni.it/userfiles/file/36676491118.pdf
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4316fd2982---57016897703.pdf
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0fa642410---1038353616.pdf
    • http://montagnobozzone.it/userfiles/files/popujoxogixer.pdf
    • https://www.saammohaseb.ir/wp-content/plugins/super-forms/uploads/php/files/a7e7a7c215ad7718bacfc9c8829fcf82/2421349126.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=witcher+best+gwent+cards
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000102b3.bin
ed9194842abe556f70efdb2033113e1d952f8418c1cd67bfad0ce7de3302bb43
pdf-font-stream PDF embedded font (sfnt) at offset 0x102B3 10704 bytes
font_01_sfnt_off00011b13.bin
299d13ed441cd41cdb3d5368adccd02bc1d61fcf926de40ee4b94d63a2cee607
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B13 17092 bytes
font_02_sfnt_off00014754.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14754 16792 bytes