Malicious PDF — malware analysis report

Static analysis result for SHA-256 da5a6548fb89d24d…

MALICIOUS

PDF

81.6 KB Created: 2021-09-05 03:03:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e1fce2564db16d6cbe6eb0198eb08abe SHA-1: 98b470e3872cff46b9888516232a1bd4554a9f40 SHA-256: da5a6548fb89d24dfbe22c64cd65a8e5bed9bdfb778fd4e0f4d6af53b629a011
104 Risk Score

Malware Insights

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

The PDF document contains numerous links, many of which point to compromised WordPress upload directories, indicating a link farm designed to distribute malicious content. The ML classifier strongly flagged this PDF as malicious, and the presence of a download button lure further supports a malicious intent. No scripts were extracted, but the primary attack pattern involves directing users to external, potentially compromised, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/e330832f7ef6365a2ce95872fc50c1c9/motenolevifef.pdf In PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/35e137f45a29f039831f79999ee93015/wipuwaperixinerom.pdfIn PDF document text
    • https://miet.hu/kepek/gowusimedibakowoxedetof.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/16121158b4f4aa---sonomonapor.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/160b092b26a928---batekubewazevof.pdfIn PDF document text
    • http://hmconcretemixingplant.ru/d/files/wejisovewasak.pdfIn PDF document text
    • http://djpress.pl/Image/files/62379573836.pdfIn PDF document text
    • https://branchennachweis.eu/userfiles/file/vuwijajiguteduxel.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/6jesqhqdhv2kmcf007copghqj4/58271222360.pdfIn PDF document text
    • http://dallapietamarchisio.it/userfiles/files/34318570277.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160852c6dad403---paziniwitiwodo.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/1612ad2e069c12---60107660793.pdfIn PDF document text
    • https://hgb.se/filer/file/zitokefatipapuditowo.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/95892880253.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16077893f750f1---mosuwireb.pdfIn PDF document text
    • https://sharpconsulting.us/app/webroot/ckfinder/userfiles/files/xexekuferurojadewanudaduz.pdfIn PDF document text
    • https://ibexquimica.com.br/ckfinder/userfiles/files/5013163085.pdfIn PDF document text
    • http://samtekelektrik.com/files/5812640800.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/ohn2michmcgf39thmlbc9eqke5/39696936178.pdfIn PDF document text
    • http://architettoseneca.com/userfiles/files/xurufekekafulono.pdfIn PDF document text
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/126408450560bdb35295d6f.pdfIn PDF document text
    • https://rumahbaruku.com/contents//files/balabow.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b257820ba1---6739483902.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=english+communicative+class+10+textbook+pdfPDF 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_off0000d61f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD61F 18008 bytes
SHA-256: f1b8e390d4ace23611b0b918d5b9cfe93dcbfc0a8cffae733e412403520ac743
font_01_sfnt_off000104ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104CE 11624 bytes
SHA-256: bf15a311ae7dc39d8a3933d2960870cda6cb234738a44f2855d1c04f9a9de2e7
font_02_sfnt_off00011fe7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FE7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1