Malicious PDF — malware analysis report

Static analysis result for SHA-256 c04d1d31d6df38cf…

MALICIOUS

PDF

74.8 KB Created: 2021-09-23 17:46:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e55e8de8f50870f3c3ad41583cee59f4 SHA-1: 1adf2629da4445326e16a9b97dc641ce2a704682 SHA-256: c04d1d31d6df38cf0ec643d3d98ea691c72c0c5752587c144572d8e59842deed
154 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The presence of numerous embedded URLs, many of which are unknown or point to potentially compromised sites, reinforces the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.5499

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 http://bebelino.ru/userfiles/file/8099821696.pdf In PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161309919d1129---gegemexufefi.pdfIn PDF document text
    • https://bdaudit.ro/userfiles/file/88482156828.pdfIn PDF document text
    • http://xn--hazrdner-r4a10d.com/alisveris/yollanan_resimler/file/89678442652.pdfIn PDF document text
    • http://canshu.dlzj.net/upload/files/20210917184607970415.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613b04f68f1cd---34327961805.pdfIn PDF document text
    • http://desushibar.com/userfiles/file/11803103720.pdfIn PDF document text
    • https://wroclawmodelshow.pl/ckfinder/userfiles/files/dufinur.pdfIn PDF document text
    • http://rapet.hu/files/duzovom.pdfIn PDF document text
    • http://dichvumucin.com/upload/ckupload/files/duwakigofajowezidevono.pdfIn PDF document text
    • http://aasghsflqsae.handylover.com/upload/files/20481149665.pdfIn PDF document text
    • https://7foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/26761193080.pdfIn PDF document text
    • https://108pizza.pl/uploads/userfiles/files/puwojumedazomixas.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614706034b734---26577937841.pdfIn PDF document text
    • http://bong-dem-long.org/upload/editor/files/20100387988.pdfIn PDF document text
    • http://healhumanity.foundation/userfiles/file/josukukog.pdfIn PDF document text
    • http://globalone-mould.com/gbw/fckfiles/20210913074759.pdfIn PDF document text
    • http://clinical-pain.com/pds/userfiles/files/wopikakoxesepudoxujibu.pdfIn PDF document text
    • https://www.retake.dk/ckfinder/userfiles/files/49978413742.pdfIn PDF document text
    • https://jfava.gemwareserp.com/userfiles/file/tasatubalu.pdfIn PDF document text
    • https://fminterativa.net/cms/plugins/ckfinder/userfiles/files/95014323263.pdfIn PDF document text
    • http://erh-hu.com/userfiles/file/dufakipilijatumajoro.pdfIn PDF document text
    • http://narcisse.sk/editor_uploads/files/dejetazibo.pdfIn PDF document text
    • http://merwepizza.com/upload/file/tadatilixaxipomujeseji.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=game+of+life+empire+instructions+pdfPDF link annotation
    • 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_off0000e6aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6AA 10920 bytes
SHA-256: d3900b6ae9774bdbd1a5b2546b3240250a7d325a908aaf0ee743d32d05e9fa69
font_01_sfnt_off0000ffeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFEB 18000 bytes
SHA-256: 4966e052a3a52e28f5cff0137306f683cd7944570df27f36d4610f49ec845076