Malicious PDF — malware analysis report

Static analysis result for SHA-256 90a83710e2b0f51d…

MALICIOUS

PDF

88.4 KB Created: 2021-07-13 20:56:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 30e06e61d61d8e8a4c831e61bd373e11 SHA-1: 710aab707b6791691beffe6794280c21ffbc4fbb SHA-256: 90a83710e2b0f51d5adeb238166a5337356d423c9c167a4ee6df21179cbe44a1
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links pointing to compromised WordPress sites, suggesting a link farm used to distribute malicious content or conduct phishing. The PDF structure itself is also noted as potentially compromised, with duplicate object bodies.

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 http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b813431a7e---ditujutexidisogewajuwav.pdf In PDF document text
    • http://staceyasp.com/UserFiles/file/tapiburixivenibikoxape.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/e7930de393303028d6f5ebf8ba86810b/88197230203.pdfIn PDF document text
    • http://klubbelgickychobrov.sk/editor_uploads/files/xajinorifitefevobiwidexo.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/4793d574f357b660612d22108e656ddb/28932014225.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff1b3e1236---mujujani.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/79c888bb6c7b20f04af7a45878365d25/96158279819.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160bcc41c7d01f---81875466919.pdfIn PDF document text
    • http://xn----7sbabaajmdfbk3ddf3azka3b6a2r.xn--p1ai/ckfinder/userfiles/files/xawoxirudatosisifovut.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/35076df12f0b13dd8bc0119201d915e5/72613184905.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/2476b547feb5e417cba3d12768e3251a/lolatolasapivelawovisad.pdfIn PDF document text
    • https://condominiovillage.com/userfiles/file/97870768691.pdfIn PDF document text
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1606f16c03c0be---zirarurofos.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607bcfb22c2c8---negumumirutegurawepase.pdfIn PDF document text
    • http://onlinemidias.com/ckfinder/userfiles/files/bisolowosomobipuzetibeni.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160945b60172bc---bagibifaj.pdfIn PDF document text
    • http://drapa-technika.cz/UserFiles/File/32842750906.pdfIn PDF document text
    • https://topupdana.com/contents//files/92899765641.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d85238a9b---46317945668.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/194a81cd0a0a8b644da83dd9bc4efe7a/dulokoditozerepiwu.pdfIn PDF document text
    • http://musikpark-live.de/userfiles/file/jitodudexagirekik.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/71782ff370f1fe22a89058a3500ca032/1870532321.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/c7b7aa3f8dd6bd6dc2fe31117bebbb59/rekof.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cf09be0cb82---pukaxega.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=mixed+effects+modellingPDF 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_off0000f25c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF25C 18696 bytes
SHA-256: 13b7a59f483029833a0909ad6c933ef4b275dfa983d975ed5abb33a04c566b7f
font_01_sfnt_off0001240c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1240C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013c23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C23 10652 bytes
SHA-256: 66e55f3b1f2646bc6620c2746fcd8cdbef592c2c2c995cd256ad902b5ff2b234