Malicious PDF — malware analysis report

Static analysis result for SHA-256 66a4425a41599dd6…

MALICIOUS

PDF

55.4 KB Created: 2021-09-06 03:01:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 7c75d7815d8cf3def338d7a97081d9ea SHA-1: 5380a59b5cf70f812137700dc6d84b25d5c9e3b1 SHA-256: 66a4425a41599dd6975e99b5998848bced2e164f1def7ffaee87932610eb3ea8
154 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content or phishing pages. The presence of external URIs and a link farm structure indicates an attempt to leverage SEO or user trust to drive traffic to attacker-controlled infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6554

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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
  • 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://irlanc.ru/uplcv?utm_term=deep+learning+with+r+pdf+github PDF link annotation
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/63b43b9b7dfd713462ef1b7dc792b83e/44340432806.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/713e26d7196a400e21ad43df89e5b01d/43093458592.pdfIn PDF document text
    • http://abwessex.com/uploads/files/29966380690.pdfIn PDF document text
    • http://ytbozhuo.com/upload/file/171830321568.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070133cd7e87---kojuzawovakuvibefikumakes.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/3cda0c9f14d8b9824044e9eb683d543e/nazonefijubawizixejoni.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/7tr5b2nourjeuoud8tc6nou5sq/kusinisemelesokefenugu.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af877777df5.pdfIn PDF document text
    • https://haysalon.com/public_html/userfiles/file/68314701676.pdfIn PDF document text
    • http://dyglas.com/userData/board/file/4571560320.pdfIn PDF document text
    • http://eskuvoiiranytu.hu/blog/file/zixelawebuvojezovo.pdfIn PDF document text
    • http://fitsiluet.cz/data/file/64495988280.pdfIn PDF document text
    • http://minuspk.ru/minuspk.ru/userfiles/file/dizakuboguvorotimewema.pdfIn PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9c3aaaa86---79619758002.pdfIn PDF document text
    • http://tourister.kr/userfiles/file/limiwuxisopowapos.pdfIn PDF document text
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/h6pvdubdrjpljat9ge2p60rhmb/dutedufefi.pdfIn PDF document text
    • http://trendybiz.in/usersfiles/file/8102938577.pdfIn PDF document text
    • http://sghscsjamarai.org/guruhargobind/userfiles/file/68974533488.pdfIn PDF document text
    • http://harlit.com/upfiles/file/bibes.pdfIn PDF document text
    • http://piotrkowska77.pl/zdjeciafile/viwegaganale.pdfIn PDF document text
    • http://www.fred-robin.com/ckfinder/userfiles/files/nofaxala.pdfIn PDF document text
    • http://www.toeterloeh44.de/files/lawakemegapuvusaduf.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4354966463---31387596508.pdfIn PDF document text
    • http://ledseoul.com/userData/board/file/zebavowavasifusoxupoporu.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/1gvolreldg0dqor5tv9v3mi0vq/16760531919.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/5c2838ed179cdc05d42ec41408d31e10/kemovulikitubutuk.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b74b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB74B 14896 bytes
SHA-256: 810dcd5847e5067ad8f100d0b5820869ae108407366ca50b91185cab4fa7d12c