Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3c7d7650ba366c9…

MALICIOUS

PDF

81.4 KB Created: 2021-09-09 11:02:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 58a9dfe1fc028aaf80a16ed9060f81cb SHA-1: c82b02f537abbeb375c04182178ff62bebbadc82 SHA-256: d3c7d7650ba366c9b4f2611594e3e315df64fae39c063f5f307f230d386a6cc9
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1539 Steal or Forge Credentials

The sample is a PDF document flagged by ClamAV as a phishing trojan. Heuristics indicate it is a link farm designed to lure users to external sites, and specifically mentions an MFA/one-time-code harvesting lure. The document body is heavily obfuscated and unreadable, preventing further analysis of its specific content, but the heuristics strongly suggest a credential phishing attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • 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://gruppocinofilomarsalese.com/userfiles/files/sujuparitutoxoboronijo.pdf In PDF document text
    • https://cursosadistanciayonline.com/medios/files/zojakekelefebefovo.pdfIn PDF document text
    • http://quangcaovuanh.com/vietkiendo/upload/file/zajog.pdfIn PDF document text
    • http://accessprecision.com/userfiles/file/61724349989.pdfIn PDF document text
    • http://agrostroi-proekt.ru/ckfinder/userfiles/files/89495280029.pdfIn PDF document text
    • http://phongthuydotho.vn/upload/files/xowogelotigonepewusosi.pdfIn PDF document text
    • http://wxdyzs.com/userfiles/files/17317313559.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/cf507aa1a8a18ae9099ee3d8fee0ecca/garexe.pdfIn PDF document text
    • http://senvietsystem.com/ckeditor/upload/files/93843784296.pdfIn PDF document text
    • http://cieplej.pl/imgturysta/file/87954351365.pdfIn PDF document text
    • http://studiotecnicoarduini.eu/userfiles/files/simipekenonopuzokunubade.pdfIn PDF document text
    • http://dakov.hu/_user/file/tifevudizujiwetinifiropax.pdfIn PDF document text
    • http://szjwwj.com/userfiles/file///texojoveturasi.pdfIn PDF document text
    • http://smenergy.kr/uploaded/file/832905927612f886539da3.pdfIn PDF document text
    • https://imaggu.com/ci/userfiles/files/wufigijenemibupero.pdfIn PDF document text
    • http://viswinkelindex.nl/images/uploads/funejikesapadipapoje.pdfIn PDF document text
    • https://www.bakkersvlaanderen.be/resources/plugins/ckfinder/userfiles/0/files/jonozuzu.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612f7dceb7461---zakogi.pdfIn PDF document text
    • https://yam-token.com/business_school/uploads/file/gujomevipobapifozukaxe.pdfIn PDF document text
    • https://lifesmart.lifesmart.ro/ckfinder/userfiles/files/zapisosolurigagofojorijuz.pdfIn PDF document text
    • https://betentour.com/sites/default/files/file/xenumumozufupi.pdfIn PDF document text
    • http://felixefontesadvogados.com.br/ckfinder/userfiles/files/xulitot.pdfIn PDF document text
    • https://groupunsur3.com/contents/files/62419181393.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/91383696650.pdfIn PDF document text
    • http://siripanyalamphun.com/user_img/files/letuluxenafofepejosub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=how+we+can+transfer+data+from+mobile+to+laptopPDF 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_off0000da2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA2A 17112 bytes
SHA-256: b82560e9c5ba73b0d417652667a3f53c4f3a1f08850119255953eb50899ec186
font_01_sfnt_off00010604.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10604 10996 bytes
SHA-256: 8b0d496e186b923699a32ebb9f0e0192527a7793ffcc9f494b05e7d413dd4c0f
font_02_sfnt_off00011f55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F55 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1