Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f395c6be11e05ab…

MALICIOUS

PDF

92.7 KB Created: 2021-08-13 04:49:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: 8673a5cd13ea34eab8a001b67511fdc5 SHA-1: e2b0e0a78d714e382dd3aff063254eaa5569c898 SHA-256: 4f395c6be11e05ab1bbc0e77fd01a5c840b47983171441457c38d23b537461a3
104 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to domains associated with link farms and potentially compromised CMS uploads. The ML classifier strongly flagged this PDF as malicious, and heuristics indicate it's a link farm on disposable hosting. While no scripts were extracted, the structure and URL patterns suggest the document is designed to lure users to external sites, potentially for further exploitation or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://enjoybowlramenandpoke.com/uploads/files/milomipelexis.pdf In PDF document text
    • https://gea99.com/ckfinder/userfiles/files/53936828420.pdfIn PDF document text
    • https://oglethorpeclub.org/~oglethor/UserFiles/file/fifasobinixinizi.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1611313246e7a7---gobelepejamakub.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/siwopazuto.pdfIn PDF document text
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/6i1rtr6niatu0jq5e89j1bahbn/36615547017.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a72e4371241---zujegutevaneku.pdfIn PDF document text
    • https://hartwellcook.com/wp-content/plugins/super-forms/uploads/php/files/b5cc22586b0d7754dea5bfb9c1d17f8b/famakajiwoworifovuv.pdfIn PDF document text
    • http://chrisdepanneservices.fr/Sites/cds/files/nusupetulizedevawi.pdfIn PDF document text
    • http://columb-sklep.pl/userfiles/file/58953025731.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/13069734473.pdfIn PDF document text
    • https://fonixkoncert.hu/upload/file/91479157196.pdfIn PDF document text
    • https://wccia-vastu.com/wp-content/plugins/super-forms/uploads/php/files/b62e877b3b0ae1ec90620a64fd25b6ad/23025815634.pdfIn PDF document text
    • https://vayamcs.com/content_files/files/61017952058.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/24992239481.pdfIn PDF document text
    • http://agendatourvietnam.com/hinhanh/file/36209087454.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/pg4onbiilec3im5p6pf6iupqi5/27472367468.pdfIn PDF document text
    • https://m-astar.com/UserFiles/files/3513184957.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/runewopisivedepipukup.pdfIn PDF document text
    • https://iohrp.org/f_files/files/16162365391.pdfIn PDF document text
    • http://nfrostov.ru/upload/files/37296684752.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/88929ac9d519486292378ee5dc3a9b13/26391815508.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=past+simple+regular+verbs+activities+eslPDF link annotation
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/1a381f3cc28509669d086d0f965a7558/83370103018.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_off00010439.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10439 10800 bytes
SHA-256: 5a8446488daffc5db512ad5d0eaa9099daf795eccbb46362fc3ebbda1bba45b1
font_01_sfnt_off00011cf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013506.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13506 17520 bytes
SHA-256: ae5ddbbaa7b2ef3b28224640c6c18189bfe4ba576da7632167559198215d75b1