Malicious PDF — malware analysis report

Static analysis result for SHA-256 af4b1f3278d95721…

MALICIOUS

PDF

83.3 KB Created: 2021-09-02 16:06:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 47a48b18fd471186207d758c062cf2ba SHA-1: c6ab6c6ff33500c5625dfaa7370fc14f90936454 SHA-256: af4b1f3278d95721043571c054d86d1e6b2214256a247c73b199fb060ff4cd3c
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to distribute traffic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of numerous unknown URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic confirm the nature of the document as a malicious link aggregator.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://unsersohn.ch/images/file/posopazozowevabufuw.pdf
    • http://lorichphoto.com/pictures/file/67919133642.pdf
    • http://khanaphatgroup.com/UserFiles/file/xitezevoz.pdf
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1608eecad82314---luzesasumezekoxuwidubiwe.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160be94eb75432---73440755331.pdf
    • http://civicwomen.com/ckfiles/files/35076569636.pdf
    • http://fxmeat.com/upload/file/bf75830d39e345c812a793fdacd1976a.pdf
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/f08d38934472f1ff886bd1da827f2fad/rixefizaruluju.pdf
    • http://thongthien.vn/upload/files/93263697284.pdf
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/06ee03e8e47941ae2ffe7e095fe1a8d2/1424780653.pdf
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609faea12c341---lipufuriguf.pdf
    • http://airsoft1.ro/files/file/xexifogufuxupalurukum.pdf
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/7g094uflf3g9v5qq3j21kno7op/bigukunovamadukuvitozawu.pdf
    • http://vistobrasil.net/uploads/file/49908570789.pdf
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607756efef6a5---18827397996.pdf
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e26c6576d43---4934898669.pdf
    • http://kimhoatra.vn/upload/fckimagesfile/49187039393.pdf
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/lc8c76hi58ug1lkqd4636hb9lq/93429090704.pdf
    • https://soechi.net/userfiles/file/86039317945.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16086e06dc243c---25150895715.pdf
    • http://toroisg.com/public/images/files/zoduj.pdf
    • https://leganordavigliana.it/uploads/file/vurijaxu.pdf
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160816d58cf70e---60641226473.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fe08856ce96---pebovi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=bmw+x3+2009+manual
    • 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_off0000dda8.bin
0ce351ecdc41241d8a87c54bd8f25a90f8aab001cffa9684e8939b6cf40e3854
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDA8 18468 bytes
font_01_sfnt_off00010e16.bin
3d252fd9601f1baaa0e76a1707214885a5dbfd5ee157d53c1b9ef2152cc0160f
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E16 10484 bytes
font_02_sfnt_off000125fe.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x125FE 16792 bytes