Malicious PDF — malware analysis report

Static analysis result for SHA-256 c948ec0775897cfe…

MALICIOUS

PDF

74.5 KB Created: 2021-10-01 09:03:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f3fc05a120102042a7e10728a70149c9 SHA-1: c944a9b9f34a58c7b5f7f349528b0aac04672a3f SHA-256: c948ec0775897cfe6f87826879e84995552165f96b7bab6146c5ae4fdfc15d99
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external links, with several pointing to compromised WordPress upload directories and other disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://synerhu.ru/uplcv?utm_term=miui+12+action+center PDF link annotation
    • https://vgi-vn.vn/app/webroot/img/files/duxepifulafasa.pdfIn PDF document text
    • http://sk-uralstroy.ru/uploads/files/92333786815.pdfIn PDF document text
    • https://yomadesign.com/userfiles/Proj_Name/files/mosibawupi.pdfIn PDF document text
    • https://adamant54.ru/userfiles/files/36134253166.pdfIn PDF document text
    • http://asliev.coco1490.com/upload/file_folder/file/72949049399.pdfIn PDF document text
    • https://eastoncn.housemember.com/uploads/files/wenex.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/686d83ca47990d09c8d87d428f9e994f/13062861519.pdfIn PDF document text
    • http://wanyuantemple.tw/userfiles/file/tovamejugomizegisevew.pdfIn PDF document text
    • http://livestreaming.group/wp-content/plugins/super-forms/uploads/php/files/e4ii1bi6d5maj4190o4g223vnd31h80h/97228261379.pdfIn PDF document text
    • http://trungtinjsc.vn/upload/FCK/file/70934286760.pdfIn PDF document text
    • https://swaarm.de/app/webroot/upload/files/narevob.pdfIn PDF document text
    • http://wcsps.com.tw/ckfinder/userfiles/files/mufufularodubivufawoz.pdfIn PDF document text
    • http://cozycornerexpress.com/uploads/files/nirososufigov.pdfIn PDF document text
    • https://360clothing.in/home/www360cl/public_html/uploads/images/files/25020247800.pdfIn PDF document text
    • http://maslatalaia.com/userfiles/file/55466195906.pdfIn PDF document text
    • http://355353.ru/userfiles/file/jakojel.pdfIn PDF document text
    • http://altus.pl/userfiles/file/simezix.pdfIn PDF document text
    • http://serbanindustrialconstruct.ro/uploads/files/pizotababatoxudomadozoxug.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614192a9d1e4d---33866175591.pdfIn PDF document text
    • http://bbdecontra.com/userfiles/files/67868253239.pdfIn PDF document text
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/fevufutomitidigu.pdfIn PDF document text
    • http://cn-noah.com/uploadfile/file/45155343886.pdfIn PDF document text
    • http://upservice.expert/admin/ckfinder/userfiles/files/ratejejiveluw.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_off0000bb14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB14 18848 bytes
SHA-256: 05d76b9d0b2aa87d46f34966668ed54d0b45e3b2dfcb4fe874744aaa321473ff
font_01_sfnt_off0000ebb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBB0 10276 bytes
SHA-256: 5fbe11ec6bec1359779fb8d10e07678e3e05bee37743e5752db5c752a56b50b7
font_02_sfnt_off0001030d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1030D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1