Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3c28ded71c9f020…

MALICIOUS

PDF

92.7 KB Created: 2021-09-13 06:46:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 0245bb20b3f6c2621a6d6f38659aab90 SHA-1: c694c046f13abf047c8c9d2216fb30f3abc0ad12 SHA-256: b3c28ded71c9f020679ba85056e00be687519bd682c2e2dac84a3da8058a0a10
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to suspicious domains and are structured to appear as file downloads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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
  • 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://unseenadventure.com/userfiles/file/kilanupavunosele.pdf In PDF document text
    • http://karpatskiles.ru/store/files/69776916001.pdfIn PDF document text
    • http://www.andreapondika.cz/file/17742441920.pdfIn PDF document text
    • http://reszke.pl/fckeditor/editor/filemanager/connectors/php/file/24252114842.pdfIn PDF document text
    • http://hndgyl.com/v15/Upload/file/20219544973078.pdfIn PDF document text
    • https://fivetc.net/uploads/files/42607425570.pdfIn PDF document text
    • http://88cpap.com/userfiles/files/35663768384.pdfIn PDF document text
    • http://elosc.com/upFile/file///ITX202109131050098570.pdfIn PDF document text
    • https://umiyawoodworks.com/fckdb/userfiles/file/64998988455.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/balijizenalopodefomite.pdfIn PDF document text
    • http://burelomdo.com/ckfinder/userfiles/files/gafotadirozirol.pdfIn PDF document text
    • http://cpbnatation.fr/fckeditor/userfiles/file/lolupasuguwilu.pdfIn PDF document text
    • http://bigbulkbags.ahmadpackages.com/survey/userfiles/files/39266443179.pdfIn PDF document text
    • http://yao-cheng.com/uploadfiles/20210903203418.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/nedanitodof.pdfIn PDF document text
    • https://gamepinleri.com/calisma2/files/uploads/nedemagobubiniwadobonona.pdfIn PDF document text
    • https://ipic.vn/userfiles/file/13341200008.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/73597594423.pdfIn PDF document text
    • https://atputasbaze.lv/images/userfiles/files/lapovenozan.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/vuvexefaxukifi.pdfIn PDF document text
    • http://cistenivytahu.cz/upload/file/durutedafavitasuxu.pdfIn PDF document text
    • http://www.alcera.ca/userfiles/file/1031476233.pdfIn PDF document text
    • http://cwpni.com/userData/ebizro_board/file/43153894583.pdfIn PDF document text
    • http://thankschicken.com/uploads/files/4773749185.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137a193bad66---42278605282.pdfIn PDF document text
    • https://milliondollardesiclub.com/upload_files/featured/files/53648514933.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=root+installer+apkPDF 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_off000103f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011c0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C0A 19088 bytes
SHA-256: 10db4ea63e4a223fe8271d1da798b01232211476c26ae7cee7c41c5c40527eaa
font_02_sfnt_off00014dab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14DAB 10384 bytes
SHA-256: a990497597994e50d3c11cafb4ff53eb2d808781deeb4a094a3b7018ba0aae10