Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5603e5d12935c7d…

MALICIOUS

PDF

93.1 KB Created: 2021-07-13 22:48:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: b7cced62d708413525ccd860799e93fc SHA-1: 88c4347d3d59211b948ce6c7d3fa1f0c8fbcb424 SHA-256: d5603e5d12935c7daff26cf87555e1cc9cb3ba053a41557d6adb9057ad1223e4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous links pointing to potentially compromised websites and disposable hosting, suggesting a phishing or malware distribution campaign. Although no scripts were directly extracted, the presence of embedded URLs and the nature of the heuristics indicate an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

Heuristics 6

  • 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
  • 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=capitulo+4a+realidades+2+answers PDF link annotation
    • http://irk-yoga.ru/upload/files/lakirufeparari.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/19f06a68a0bcfa0d77b0b8d09dc89158/60648536000.pdfIn PDF document text
    • http://fitviewer.de/files/file/61696211528.pdfIn PDF document text
    • http://baohanhranghm.com/upload/img/files/pofafufixamimaponokufew.pdfIn PDF document text
    • http://neurooperations.com/ckfinder/userfiles/files/xorepikekuzuz.pdfIn PDF document text
    • http://componentcnc.hu/uploads/ckfinder/userfiles/files/88495686631.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160bc8e6564bf4---demozesekibikigolatuseza.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609cebaae22a6---sujabaletopukulije.pdfIn PDF document text
    • https://www.northwoodmedical.ca/wp-content/plugins/super-forms/uploads/php/files/abbqk99vj1m4r7j433tdl82pf7/76902706047.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/83092813134.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16093bd5717e43---22548742069.pdfIn PDF document text
    • https://mabuksusu.com/contents//files/96000002860.pdfIn PDF document text
    • http://tatugigo.com/ckfinder/userfiles/files/gupisoxowujiwinopo.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095d6c900e27---52610469554.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/42722610312.pdfIn PDF document text
    • http://baliretreatcenter.com/olabali_ci/media/images/newsfiles/92741692047.pdfIn PDF document text
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/80471693832.pdfIn PDF document text
    • http://speaklifeiamgreatness.com/files/files/81955754537.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607329d0aa9c2---48237197975.pdfIn PDF document text
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/kegujazuvewevaximosabube.pdfIn PDF document text
    • https://ngoctraithaibinhduong.com/uploads/news_file/dikexafafu.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/nerolovasid.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b1746e726f---dozapi.pdfIn PDF document text
    • https://limsurdua.com/contents//files/xibetim.pdfIn PDF document text
    • http://leadershipcareer.kr/fckeditor/_upload/file/jufobeluxubuverupelam.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_off0000ffcf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFCF 21408 bytes
SHA-256: dfb9f8adbd990497b6b81ad4bbbb177a656594b055463c999c877f8b324d1d5f
font_01_sfnt_off000135a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135A3 10800 bytes
SHA-256: 13b4b7c1a619529434dd4f9f1f7c4bba456405d8adb85b50710a2218b5e58723
font_02_sfnt_off00014ed0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14ED0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1