Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3d18cf6b113b470…

MALICIOUS

PDF

69.0 KB Created: 2021-09-03 10:30:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 68d9c468596739218c33a458d5956c63 SHA-1: 98cff9fa4340d5d4ef30da9c88cf7a66c0598fcf SHA-256: c3d18cf6b113b470b1d8da1c8c964d57dc270a9d1377af5a782bcadf199b8c3a
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. It contains numerous links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users. The presence of external URIs and link farm characteristics points towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6872

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
  • 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://bephoangdung.vn/uploads/ckfinder/files/12850088566.pdf In PDF document text
    • https://suprizpin.com/calisma2/files/uploads/62618035640.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/0a1c8eeeac2692c1187611658f1bfdfc/31192131823.pdfIn PDF document text
    • http://futurepoolandspa.com/ckfinder/userfiles/files/55872910120.pdfIn PDF document text
    • http://shsclassof1959.com/clients/a/a7/a7a82b2a6025f7fafce5d77be70bf845/File/xosukegumozerubixed.pdfIn PDF document text
    • https://quatcongnghieput.com/uploads/files/71293677337.pdfIn PDF document text
    • https://swagath.co/new/ckfinder/userfiles/files/tijalunutosorisik.pdfIn PDF document text
    • http://nbc.com.vn/ckfinder/userfiles/files/tulowonigovuf.pdfIn PDF document text
    • http://zuszdounky.cz/files/58846488406.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/firawatuvole.pdfIn PDF document text
    • https://traonguoc.vn/wp-content/plugins/super-forms/uploads/php/files/3nr8fih7dfiq7mf7pc7d03r9pn/vivizufote.pdfIn PDF document text
    • http://swissies.lt/ckfinder/userfiles/files/mevofokewofekor.pdfIn PDF document text
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/13379555743.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160984d946b373---vodumoliraliwu.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160dc08e7a0c1c---gododez.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a8b70c19ef2---fezijas.pdfIn PDF document text
    • https://aarhuskortet.dk/images/file/38320873553.pdfIn PDF document text
    • https://rinducm1.com/contents//files/zozuwegoj.pdfIn PDF document text
    • http://daiichilogistics.com/uploads/news_file/85598367155.pdfIn PDF document text
    • http://ayrh.internet-match.com/upload/files/98403498959.pdfIn PDF document text
    • http://zhuoer.ltd/userfiles/file/nusevutodijufug.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/91786dccb4ff943069d7713178dca620/regivosu.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/b03662e89630b7c8d0775a59334612bc/bulurajemujibududewewevi.pdfIn PDF document text
    • https://seikai.jp/free_images/files/widinovilefek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=decoding+words+grade+1+worksheetsPDF 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_off0000c913.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC913 10836 bytes
SHA-256: c5b18614ec1da4bd29c3f2c8a776112ba11daf1815949219de5aa596ab19263a
font_01_sfnt_off0000e1f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1F1 17580 bytes
SHA-256: 2de063336e8e6dd58c0f5fea85e883a784ed2af99ef4c7cd42e30a2f31161cfa