Malicious PDF — malware analysis report

Static analysis result for SHA-256 944d637eafafc656…

MALICIOUS

PDF

85.0 KB Created: 2021-09-12 20:36:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 739611ccabeb0bad92af492120b5e222 SHA-1: a769aa702fe79c3535d860818de8095d83c6cea9 SHA-256: 944d637eafafc6561903f3c76f4e2e68eb317791fb499ea0254c93c5d94ccc88
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The sample also exhibits characteristics of a link farm, with numerous URLs pointing to potentially compromised WordPress sites and disposable hosting, suggesting an attempt to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pn-tech.net/userData/board/file/30244221137.pdf In PDF document text
    • http://kristiankutschera.de/userfiles/file/81321313899.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/7157cb0c3e19efcd7e1007461e0e64f6/gupadadusapupas.pdfIn PDF document text
    • http://self119.net/upload/userfiles/2021/09/files/210912215945.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/711c40303a5af13cf85728009cc04667/supadejagopowewutibaxu.pdfIn PDF document text
    • http://lightningriskassessment.com/ci/userfiles/files/zozofip.pdfIn PDF document text
    • https://irepairplus.nl/app/webroot/files/userfiles/files/rulawovadufapifevuko.pdfIn PDF document text
    • http://rama-sp.com/rama/webroot/js/ckfinder/userfiles/files/bezaridutesida.pdfIn PDF document text
    • http://www.plain-pied.com/editeur/ckfinder/userfiles/files/41819879688.pdfIn PDF document text
    • http://innospectrum.eu/hirlevel/file/75617117382.pdfIn PDF document text
    • https://elmaga.lt/components/com_mijoshop/opencart/image/data/files/21457040200.pdfIn PDF document text
    • https://mtydizayn.com/userfiles/file/73960550793.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/fcd1b5151a99563c130bcdcae3bd8ac2/rogitobekonowuvejoloj.pdfIn PDF document text
    • https://llbyggodesign.se/UserFiles/files/38493033.pdfIn PDF document text
    • http://shqinze.net/admin/upimg/file///fowadosenerufuniluzul.pdfIn PDF document text
    • http://antasboru.com/guvennet/resimlerfiles/46326309039.pdfIn PDF document text
    • http://xlpe.net/Images_upload/files/dofedujapoposavolixo.pdfIn PDF document text
    • http://es-manzokudou.com/yamituki-n/uploads/files/vidadomuxelumijob.pdfIn PDF document text
    • http://ekotop.eu/userfiles/file/gedesebonilesesedosukolaf.pdfIn PDF document text
    • https://www.pelicanfinancialnetwork.com/ckfinder/userfiles/files/77693495003.pdfIn PDF document text
    • http://www.nomorcantikjoss.com/file/78358493239.pdfIn PDF document text
    • https://pcetravel.com/files/file/44458927789.pdfIn PDF document text
    • http://markfarolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/27962651422.pdfIn PDF document text
    • https://livnica-metalurg.com/images/pages/file/22347550529.pdfIn PDF document text
    • http://paraglider24.de/pics/fotos/1/file/sifuvuxagepakitanad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=slope+76+unblockedPDF 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_off0000e84b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE84B 10512 bytes
SHA-256: e1c84866914f67b01ff389603151c68dea127ef7973f2996eed388f4fed4aa0e
font_01_sfnt_off0001002b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1002B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001183d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1183D 17692 bytes
SHA-256: 69f5c348cb8c85dec77aa3139a1346401452c0cd38f350170def0b8f08f12e6f