Malicious PDF — malware analysis report

Static analysis result for SHA-256 35100de700e6a6ec…

MALICIOUS

PDF

79.6 KB Created: 2021-09-21 12:29:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 31677169787e6398232938c5183c339d SHA-1: 03621f4811f6c10ca3715a2755d98865312eb986 SHA-256: 35100de700e6a6ece252dfcc8d5f864b3ca197fa188e867501bfc76e35726d2c
72 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and a large number of external links, many pointing to compromised CMS uploads and disposable hosting. The primary link, 'https://smidgel.ru/uplcv?utm_term=karate+king+game+download', suggests a lure to download a file. The embedded JavaScript likely facilitates the execution of a downloaded payload or further redirection, contributing to a client execution attack.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.3497

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.
  • 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
  • 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://smidgel.ru/uplcv?utm_term=karate+king+game+download PDF link annotation
    • http://cokhiminhhien.com/media/ftp/file/25041981579.pdfIn PDF document text
    • http://ng-sons.com/userfiles/file/84946428244.pdfIn PDF document text
    • http://naturpix.ch/cmsimages/file/45620128994.pdfIn PDF document text
    • https://infotechsystemsonline.com/ital/www/img/file/14279724321.pdfIn PDF document text
    • https://tattica.byespresso.com/app/webroot/files/upload/files/79885248129.pdfIn PDF document text
    • https://www.rongoldmanlaw.com/system/js/back/ckfinder/userfiles/files/79246295697.pdfIn PDF document text
    • http://self119.net/upload/userfiles/2021/09/files/210914175019.pdfIn PDF document text
    • http://portaldeaquidauana.com.br/ckfinder/userfiles/files/65677142137.pdfIn PDF document text
    • http://newo.ru/files/files/6638570602.pdfIn PDF document text
    • http://brukikostka.pl/uploads/page/file/kewetepiratobogulasoduno.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/d1aa3dde735703231a285b645e427e33/vidowuku.pdfIn PDF document text
    • http://akekaluck.com/ckfinder/userfiles/files/vozonaroronutomosobak.pdfIn PDF document text
    • http://mkconline.com/landmark/ckfinder/userfiles/files/nanufesojuxono.pdfIn PDF document text
    • http://maduraicaterers.com/app/webroot/js/ckfinder/userfiles/files/41692533522.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fe562f14d6---8223829800.pdfIn PDF document text
    • http://thesei.com/In PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613f9fafb75ba---77060298063.pdfIn PDF document text
    • http://ecohost.ru/pics/images/file/69124860752.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f09739a6e1---46206471782.pdfIn PDF document text
    • http://colegiosantarosa.com/uploads/imagem/file/97341584160.pdfIn PDF document text
    • http://resheto.ru/users_images/fck/file/midoxubekenosugawiruro.pdfIn PDF document text
    • http://npas.ru/pic/file/63687458808.pdfIn PDF document text
    • https://georeno.ca/userfiles/files/6690705982.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ecc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECC4 17772 bytes
SHA-256: a7276a96cf68092a58c6b4d7aa79a075620a6c12592d62c8363651c4fb2e5b57
font_01_sfnt_off00011a82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A82 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1