Malicious PDF — malware analysis report

Static analysis result for SHA-256 6cb8d90a271cb21e…

MALICIOUS

PDF

79.8 KB Created: 2021-09-16 15:44:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 99456159e9621e545b8abb29bb3d139b SHA-1: 880103a93c37062d873d42e6712f957b1046cd92 SHA-256: 6cb8d90a271cb21e443e741bf34e2795149ada2fea850d0ebb8da57448afb2fd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the PDF structure itself facilitates the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://crewmak.ru/uplcv?utm_term=jetpack+joyride+mod+apk+happymod
    • http://gavinlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/68525017992.pdf
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/8b24u2538ancmbu4vkd1fcjhif/xekiforaninafonugepevulo.pdf
    • http://satcomlink.com/userData/board/file/xizukowoxu.pdf
    • http://xn--e42bt3l.net/upfile/files/xatugupogixo.pdf
    • http://harlit.com/ckfinder/userfiles/files/20210902_025740.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d6c613efa0---birizojugonolinoroke.pdf
    • https://booknowrentalimo.ch/userfiles/files/38150152488.pdf
    • https://cashcruis.ru/wp-content/plugins/super-forms/uploads/php/files/75f94112a02e951447914cd0d82aecb2/fawirivufib.pdf
    • http://mecateengenharia.com.br/ckfinder/userfiles/files/88358808994.pdf
    • http://elturo.ru/img/upload/files/kigixiwunedovusenato.pdf
    • https://alstar.uz/images/shared/file/zasirazuzekituzemosir.pdf
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/161411e45f2baf---72208576447.pdf
    • http://vilocom.net/webroot/img/files/guzenametiditososuz.pdf
    • http://jinsonmetal.com/Upload/file/32431381070.pdf
    • https://korankertas.com/contents/files/9565313195.pdf
    • http://i-physiology.ru/upload/rovorepotu.pdf
    • http://lawyermo.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pebitopuzagorikexalu.pdf
    • http://tubietelbar.hu/uploadfile/55985350727.pdf
    • https://butzbacher.turnpoint.jo/app/webroot/upload/files/wugesara.pdf
    • https://mintowncoffee.net/uploads/images/files/99721880984.pdf
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/974ndege8gdb7l66bbj0lnkpc3/56679439376.pdf
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/f5a957056524dd710779f883fb7c666b/12605954853.pdf
    • https://cincia.ro/ckfinder/userfiles/files/wopovadotofatigadaneb.pdf
    • http://www.satunatc.ac.th/ckfinder/userfiles/files/tugekulugekuvifukejel.pdf
    • https://vegan-eshop.cz/data/file/84210144858.pdf
    • http://magdrywall.com/project-new/christianbook/upload_images/file/kezefeve.pdf
    • 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_off0000d4cf.bin
7fc84794a05ecf61dc8a4cfbf888595a3f5e4f600fe96a1253c74c4d8b1aec9f
pdf-font-stream PDF embedded font (sfnt) at offset 0xD4CF 16828 bytes
font_01_sfnt_off00010030.bin
88d3c48ffe127694d84a24890986ef0b6f6b654bd446d38f3cdfd1c3134568cc
pdf-font-stream PDF embedded font (sfnt) at offset 0x10030 10788 bytes
font_02_sfnt_off00011915.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11915 16792 bytes