Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f3be9dcb8172818…

MALICIOUS

PDF

74.2 KB Created: 2021-09-24 12:58:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 2e93252d36e1a8e447f8ca4770246232 SHA-1: 0976fdefae9d2de4a599945559e825258a127219 SHA-256: 6f3be9dcb8172818618aff937763eddd93989810feabd1a95b929d2cdf8685ff
126 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous embedded URLs, many pointing to disposable domains and configured as a link farm, suggests a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with attempts to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ytovietnam.net/ckfinder/userfiles/files/solipuvojubosevupudo.pdf In PDF document text
    • http://fskyok.com/uploadfile/files/pafujoxometavubonuteteve.pdfIn PDF document text
    • http://www.facyt.com.ar/ckfinder/userfiles/files/jewinudoridaf.pdfIn PDF document text
    • http://phuquytravel.com/nguyenvanlinh/files/dagirugezonadebuz.pdfIn PDF document text
    • http://jobcred.com/rk/jobcred/uploads/image/file/65655179057.pdfIn PDF document text
    • http://standardamulet.com/files/files/98913176382.pdfIn PDF document text
    • http://yesfabric.com/images/upload/File/158894882.pdfIn PDF document text
    • http://sztarmedia.hu/_user/file/97363127686.pdfIn PDF document text
    • http://isagenixmakessense.com/ckfinder/userfiles/files/voboxeforifemufepulas.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/dafaxar.pdfIn PDF document text
    • http://ricoconsultingattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/51395635429.pdfIn PDF document text
    • http://ombs.ru/uploads/files/jivudevuveguwuzugazotukeb.pdfIn PDF document text
    • https://andymullinscommercial.com/home/andy/public_html/ckfinder/userfiles/files/81875491350.pdfIn PDF document text
    • https://baruipur.org/ckfinder/userfiles/files/35681804724.pdfIn PDF document text
    • https://kameramuzesi.com/upload/files/xuzebaloked.pdfIn PDF document text
    • http://morebricks.com/ckfinder/userfiles/files/buxopaji.pdfIn PDF document text
    • http://vrakskodamnetice.cz/file/xoperinem.pdfIn PDF document text
    • http://ttworld.hu/uploads/content_files/files/41386633392.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0676784bb---xakalutowi.pdfIn PDF document text
    • https://www.hosotte.com/ckfinder/userfiles/files/76127756025.pdfIn PDF document text
    • https://eccdc.org/application/webroot/userfiles/file/rugukisuvelufilexerovep.pdfIn PDF document text
    • http://www.beverburcht.nl/upload/files/53577742906.pdfIn PDF document text
    • https://4cmedica.com/ficheiros_upload/file/38451602598.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/e6d6fc235fce82708453f112694345cd/28357129827.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=android+screen+does+not+rotatePDF 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_off0000b9db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d1f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1F2 10296 bytes
SHA-256: 9f4859d278bf529bfd0c0e3eeecb537bba08a809c775bc1d24b64f66fefde31e
font_02_sfnt_off0000e948.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE948 19436 bytes
SHA-256: e426294fc8bdccaf0bcd2f63228d5773fb074882b376821ee6eafe4106a90843