Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4893ea7dd5d69a8…

MALICIOUS

PDF

86.3 KB Created: 2021-06-29 07:33:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 880122d864ba4e356a8beeef3e562056 SHA-1: b0e1494fa62856df4837a4d506f461b042c88959 SHA-256: c4893ea7dd5d69a879a64b33742e01a0f463fda04fef55339759dc1d3c5f40c2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites, which in turn host other PDF files. This pattern suggests a link farm designed to obscure the ultimate destination, likely a phishing or malware distribution site. The ML classifier and ClamAV detection strongly indicate malicious intent, with the primary attack pattern being the use of a link farm to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c9033024bf7---latametitivi.pdf
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/16098c2e41a570---rifujijawatezugateloka.pdf
    • https://bruceautoservice.com/files/file/vokidurufuvo.pdf
    • https://netiko.ge/img/Data/file/2168541047.pdf
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/7163c56f3fe149474c190910dc2936fe/veletenut.pdf
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/00f8e48d51423e9232439b8b1e61b73c/389242857.pdf
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/vemnb4699pj8dnnuvure8l7l35/32747099151.pdf
    • http://samafb.org/uploadfilefiles/dorizudulagoja.pdf
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/jsaplnulgn01p612n4h6cetf1a/kinobadixalepunuledimirof.pdf
    • http://termocity.by/pics/files/ketidado.pdf
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/558c5cdd28212a9440c9b66b07a4ac4f/jaladufavatenovinub.pdf
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1609e0616a954a---lebuzapegazibipenu.pdf
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160b1a47d7fbd0---22271507507.pdf
    • http://jnafarms.com/clients/864068/File/47025494841.pdf
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160950c1c36f4e---jofezagokolapinavobez.pdf
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160715ac6c565d---sulurerawawu.pdf
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1608557f729667---51985825083.pdf
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c66369d0474---bovajuriwudajowofavir.pdf
    • http://clarksville.net/wysiwygfiles/file/41405025839.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aafb682cecc---2800031220.pdf
    • http://sllight.ru/design/img/upload/file/lanagufomuputesopixozesod.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/1f9bf9948d6aebb85b2c418535b04df5/76433423619.pdf
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609c28e2475ae---zadatedopogirebevetob.pdf
    • https://mariellatriolo.it/public/file/47022754237.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=vitrectomy+for+floaters
    • 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_off0000f0c5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C5 16792 bytes
font_01_sfnt_off000108dc.bin
2203a8c3db2ebab85499f9fce47133d0abfb0334bbbb1107e9f751edc5c109ce
pdf-font-stream PDF embedded font (sfnt) at offset 0x108DC 10476 bytes
font_02_sfnt_off000120c1.bin
ff22a36e8ca23aa8e51fa733c226a50c60c464fd77fdd7c2fa7d63237a33f564
pdf-font-stream PDF embedded font (sfnt) at offset 0x120C1 16680 bytes