Malicious PDF — malware analysis report

Static analysis result for SHA-256 919a5e549fbdd1a3…

MALICIOUS

PDF

70.9 KB Created: 2021-10-02 00:45:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 05d2b7af3ebd4467003592ffe5c0cbd2 SHA-1: 52e93a2e4d9634888fef1dbcb4789a9c206c80c1 SHA-256: 919a5e549fbdd1a3935f579525b54148d34a8f8a1517bdd4fcbf272edb213e93
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to manipulate search engine results or distribute malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a potentially harmful link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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 http://galerie45.com/userfiles/file/87338248695.pdf In PDF document text
    • http://expnavi.com/sites/all/sites/default/files/file/tupiledidanal.pdfIn PDF document text
    • http://gewidor-gmbh.de/uploads/files/80453203459.pdfIn PDF document text
    • http://thongthien.vn/upload/files/57728381054.pdfIn PDF document text
    • https://giridhareye.org/ckfinder/userfiles/files/86365676065.pdfIn PDF document text
    • http://websurin.net/UserFiles/File/28693915838.pdfIn PDF document text
    • https://baongochoa.com/upload/file/33540161816.pdfIn PDF document text
    • https://florerialafloresta.com/ckfinder/userfiles/files/fivex.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/lolebapujejirukonuwopog.pdfIn PDF document text
    • https://thefertilizerproductionline.com/d/files/90439512561.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/161304cff8396a---gelija.pdfIn PDF document text
    • http://pronobile.de/catalog/file/52989414851.pdfIn PDF document text
    • http://dental-forum.ru/userfiles/file/73218620551.pdfIn PDF document text
    • http://occahomesearch.com/userfiles/files/telofakapunikiwasazalo.pdfIn PDF document text
    • http://moriefrusca.com/userfiles/files/87499614827.pdfIn PDF document text
    • http://www.icareonline.net.au/ckfinder/icare/files/14695327406.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615687d658a5b---87034687455.pdfIn PDF document text
    • https://fruitssupplier.com/app/webroot/img/files/fidojazi.pdfIn PDF document text
    • https://elpollopaulino.com/cenavarra_userfiles/files/tegujudipowavu.pdfIn PDF document text
    • http://ccshecea.org/upload/files/nolosagizabil.pdfIn PDF document text
    • http://osoboebludo.com/ckfinder/userfiles/files/berime.pdfIn PDF document text
    • https://keluargamimpi.com/contents/files/vikinadefa.pdfIn PDF document text
    • https://istanbularicilikfestivali.com/upload/ckfinder/files/82632577406.pdfIn PDF document text
    • http://www.ettermanenterprises.com/ckfinder/userfiles/files/rupuwilakaw.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614583f358e10---12768562708.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=como+bajar+videos+de+youtube+a+mi+celular+androidPDF link annotation
    • http://perfecturology.cafe24.com/upload/editor/imagefile/46076348102.pdfIn PDF document text
    • 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_off0000b45e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB45E 15480 bytes
SHA-256: 4b44cbd68f17795f5d8515eb42814690f8af8f105f5bf5fc2706fbede0c68237
font_01_sfnt_off0000db99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB99 11112 bytes
SHA-256: f08823af23ca0ea2a06e5b0c1ca1252ef866ceb511bd6766c66f8cba3ff88977
font_02_sfnt_off0000f58d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF58D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1