Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d5b2370bdc0db98…

MALICIOUS

PDF

85.6 KB Created: 2021-09-21 09:27:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 086c63961941dc375d25b41ef3fa369f SHA-1: 8583ea9a3f9647f41314feb740a5de6d690ae372 SHA-256: 3d5b2370bdc0db988a588ef22c5041aa03e708b9cf0415a34b089ccb08c8bb64
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is a PDF document identified as a link farm, containing numerous URLs pointing to various websites. The ML classifier strongly indicated maliciousness. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to lure users to potentially compromised or malicious sites, possibly for SEO manipulation or further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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://5uempat.com/contents/files/nuvurekevas.pdf In PDF document text
    • http://pop-around.com/file_media/file_image/file/sazivamowali.pdfIn PDF document text
    • http://bolt.fo/public_html/userfiles/files/4968877657.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/6d15a68caa9feb049f824d24ef7ed75f/juwokivit.pdfIn PDF document text
    • http://hyundaidongdo3s.com/images/files/80032496983.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/jadofadanowovelaj.pdfIn PDF document text
    • https://aymfly.com/aym_image/files/48729661225.pdfIn PDF document text
    • https://thaiwoodengames.com/files/upload/files/dikufu.pdfIn PDF document text
    • https://lawweb.info/mycms/admin/userfiles/file/jemupukemuwezalegikenobi.pdfIn PDF document text
    • http://technoprofile.ru/userfiles/file/5705526584.pdfIn PDF document text
    • https://arendic.cl/files/jarol.pdfIn PDF document text
    • http://iviltra.lt/images/files/xodiloloraxodopafokoboxas.pdfIn PDF document text
    • http://a-xian-coat.com/uploads/files/202109112311254857.pdfIn PDF document text
    • http://mitsubishilongbien.vn/images/ckeditor/files/6375948063.pdfIn PDF document text
    • http://leasingtowers.com/ckfinder/userfiles/files/rofepusazug.pdfIn PDF document text
    • http://studiochiodo.eu/userfiles/files/77023113332.pdfIn PDF document text
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613910e976fe5---34996833635.pdfIn PDF document text
    • https://tommytest.dish1314.com/data/html_editor/files/wezil.pdfIn PDF document text
    • http://geomanteia.com/userfiles/files/padudigemitusuninabajuwe.pdfIn PDF document text
    • http://goldenpeak.it/userfiles/files/17102683408.pdfIn PDF document text
    • https://milorem-service.ru/userfiles/file/99830710670.pdfIn PDF document text
    • http://binhchuachay.info/Images_upload/files/gipujiwuxamarunukalaxivul.pdfIn PDF document text
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/2d3c194e8c8f2154a564325d45ef46dc/8846922039.pdfIn PDF document text
    • http://kondicionery-elektrostal.ru/upload_picture/file/75551778541.pdfIn PDF document text
    • http://rvhifi.cz/files/file/pifowoxutavoreliw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=android+phone+font+changerPDF 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_off0000ea16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA16 17620 bytes
SHA-256: 17d8b69cf356e07ccf0ef9274fcaa67f1967dc4b493b89b50bd9f4e8b6efd657
font_01_sfnt_off00011831.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11831 10668 bytes
SHA-256: 210a5ad256fa535d6334a485440bafec016b3e2cefe4283358acd7eef132aa65
font_02_sfnt_off0001305c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1305C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1