Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9b3c659c88ae35f…

MALICIOUS

PDF

75.5 KB Created: 2021-07-23 23:05:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: effcb7ffc6e43cc82822054a83af15e4 SHA-1: 2f044e636014f0ff5026b2b7f27c740aa3445fa2 SHA-256: f9b3c659c88ae35f549646cf30b3b80ff867c4b699c0fe15ca950f40e48239cc
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous URLs, several of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document's structure and URL distribution suggest it's designed to lure users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ufnk.fr/app/webroot/files/file/fululuvizukidirasi.pdf In PDF document text
    • http://podwierzba.eu/ckfinder/userfiles/files/43996645363.pdfIn PDF document text
    • http://rivieahk.com/clients/5/51/51325344bd1517f257d6959d5350918e/File/33671264507.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/a5ed20d26ba6e43ecfb157b13bcd7083/94346300507.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bbb0e08b1fe---fasikizefixifibasamiw.pdfIn PDF document text
    • http://3sdent.com/upload/files/nonuf.pdfIn PDF document text
    • https://rajatotogroup3.com/contents//files/kexekenigipilala.pdfIn PDF document text
    • https://coatielectronica.com/files/95966814837.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/1608561499f7c6---wagebulobiwig.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c37869588c2---wejawedivusirulovakud.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/160b45b2e33e89---mugazezuzowelixepaz.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/5f6qrumpdmrt38gn9n9n1kdrm0/wedopogaboraxuramatotula.pdfIn PDF document text
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/9fafa07eb5b5906c361360a1a9e783d7/27748014785.pdfIn PDF document text
    • http://www.colormotion.cz/UserFiles/file/50396600682.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607856b807717---70157518685.pdfIn PDF document text
    • https://farmaciasacoor.com/site/upload/file/zabopotiwexudukuvifasevi.pdfIn PDF document text
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082c584b4fed---doxaxilet.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=what+are+adversaries+in+the+biblePDF 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_off0000c38b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC38B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dba2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA2 10424 bytes
SHA-256: 87ab90d3c4e67072cda52d11876b067760b2ccc02a6d771df7d9c7b04530e181
font_02_sfnt_off0000f332.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF332 17196 bytes
SHA-256: caaf66cb3bb43d46af8c532f5c54bdc4091925ec3661bbf874531d38fa60a1b6