Malicious PDF — malware analysis report

Static analysis result for SHA-256 87d2d8109466519e…

MALICIOUS

PDF

76.9 KB Created: 2021-08-29 17:16:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: ba98b865d55726e6d38bdad6098f9f4e SHA-1: e79303764ce4fe445493a0115e11c5404ffde532 SHA-256: 87d2d8109466519eb46360c77a0a4c8e68aaf137624e47976cd06590cc635b49
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a phishing or trojan threat. It functions as a link farm, with numerous URLs pointing to compromised CMS upload directories and disposable hosting domains, likely intended to lead users to malicious content. The presence of multiple PDF link farm heuristics reinforces this assessment.

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 http://velkoobchod-man.eu/ckfinder/userfiles/files/33282824589.pdf In PDF document text
    • http://concept-art.nl/app/webroot/files/userfiles/files/10140803254.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16077f909e78de---vasavelerevok.pdfIn PDF document text
    • https://zevkotodoseme.com/upload/ckfinder/files/vazovoretezifada.pdfIn PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160859571476bc---79971457274.pdfIn PDF document text
    • http://neilreardon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/72424071483.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/16094ca1862138---ranebefowagu.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/16087a7e126e3a---93925210602.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/s298q4d37r7qllt8tep5gpm4f3/20775584866.pdfIn PDF document text
    • http://alexforstarlight.com/clients/4/41/4125d763bdae894b2c088b8c4c0f4705/File/86453435613.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160814c5cab410---73151132216.pdfIn PDF document text
    • https://wodepcb.cn/uploadfiles/files/44148636944.pdfIn PDF document text
    • http://ofitecnic.es/files.ofitecnic/fck_up/file/biruxaz.pdfIn PDF document text
    • https://rajatotogroup1.com/contents/files/29051531282.pdfIn PDF document text
    • http://zelene-centrum.cz/webpagebuilder/ckfinder/userfiles/files/59793674861.pdfIn PDF document text
    • http://ashole.hu/UserFiles/File/zesexegi.pdfIn PDF document text
    • http://unionnutritech.com/upload/files/51722759308.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098a8484850d---jasarinuwukepuwagewe.pdfIn PDF document text
    • http://pascalparrot.com/uploads/assets/file/gopomerijobekobedof.pdfIn PDF document text
    • https://wisserarm.nl/app/webroot/files/userfiles/files/lanorepafeleju.pdfIn PDF document text
    • http://ahchala.com/img/file/22520829403.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1610eda11d8de8---jerojatibi.pdfIn PDF document text
    • http://ministerium.pt/files/40115094876.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d307853286---80539684329.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=force+acceleration+graphPDF link annotation
    • 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_off0000c9f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9F3 10460 bytes
SHA-256: 870c463e1d1452e576a58a12ac661040e12ab9191b6c66b0bbb07daa7e1eca22
font_01_sfnt_off0000e18d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE18D 17216 bytes
SHA-256: f1684d0cc05ca7c2177d99899910c75368f9e6433e6006bd79506fbcd488451e
font_02_sfnt_off00010e62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E62 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1