Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a7e5b6f76ca6e84…

MALICIOUS

PDF

84.4 KB Created: 2021-07-02 15:22:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: ffdf656a3fc9705414efa45103f565d3 SHA-1: 622f44ec338b68770146d52a9c3a6051bbd02949 SHA-256: 6a7e5b6f76ca6e84b77f0fa6456bef2f289fd043231aee53341e6a82f7810eea
96 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to other PDF files hosted on various domains, indicating a link farm. Several heuristics suggest these links are part of a compromised CMS upload or a disposable hosting setup, likely for SEO manipulation or to distribute further malicious content. The ML classifier strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://livinglearningandworking.org/clients/e/e0/e05af8355f71d8da3aa90f500b9284b3/File/makaboxakal.pdf In PDF document text
    • http://eko-inwest.eu/upload/file/ninejufalip.pdfIn PDF document text
    • http://consulcongress.it/uploads/assets/file/60592609247.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/15906400368.pdfIn PDF document text
    • http://ajivikafinance.com/userfiles/file/95314570050.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608687b10df26---nusep.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/6f4b9n98g5u3ma7mpre7eg4lra/tepujavoda.pdfIn PDF document text
    • https://cvsc.co/userfiles/file/86973794453.pdfIn PDF document text
    • http://rauvuonsach.com/images/uploads/files/85446693686.pdfIn PDF document text
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/seh28m1anbu38k0tef38vto2n8/30603396489.pdfIn PDF document text
    • http://watthaistuttgart.de/userfiles/file/39989250204.pdfIn PDF document text
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/6fkpulpuc8ar24idq0qjv81b0j/lixabupevodujufog.pdfIn PDF document text
    • http://elcampoeco.org/FCKeditor/file/869191249.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b143b971c9b---81100812303.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/1d619e0c8c3be0253e7443f8d9adc3b2/dodomuduzugoran.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/3d1f6cdbv4sb199u29rpji1s96/52454230732.pdfIn PDF document text
    • http://nemdanangpho.com/uploads/2021-06-11/images/files/69424728136.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/16073864cb10fc---rovexusubivamoseso.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/e1c3168d3c4402559bb07c6d5faffe3c/jurijuvajogev.pdfIn PDF document text
    • http://world-spa-resorts.com/dok/meribonijekena.pdfIn PDF document text
    • http://amoy-art.com/Upload/file/tosodalanevufo.pdfIn PDF document text
    • http://hoteldanang.vn/uploads/images/files/79650732186.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=pinched+nerve+in+leg+and+footPDF 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_off0000e98c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE98C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001019e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1019E 16476 bytes
SHA-256: 59c8d9bc3301ba7dd5d6527fa3782192c6bdeb28150eb580b81eb8caaf7f1442
font_02_sfnt_off00012c48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C48 10652 bytes
SHA-256: d3a2f4c5fd176774f06cc62357fa10d87059c91ebd4c28636cb8a178dc85e5bf