Malicious PDF — malware analysis report

Static analysis result for SHA-256 29c418c3853e2c54…

MALICIOUS

PDF

83.4 KB Created: 2021-09-20 08:25:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a9fe3d6cfbe489f512e381e871793edc SHA-1: abf79ed2bd48092b3e3dad65cf1c882e07ac5780 SHA-256: 29c418c3853e2c5448cc5ba7b40033bd7753c7b103cc4b823f6b1a1cd0d481aa
174 Risk Score

Malware Insights

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

The PDF contains numerous links to external PDFs hosted on various domains, many of which appear to be disposable or low-reputation. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a deliberate attempt to create a link farm on such hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://goodmix-psc.com/userfiles/files/48541000686.pdf In PDF document text
    • http://app0.linkeo.it/ckfinder/userfiles/files/61275053984.pdfIn PDF document text
    • https://nevjegyzek.eu/uploads/file/pejove.pdfIn PDF document text
    • http://talleresjpg.es/img/file/95441630471.pdfIn PDF document text
    • http://qdsenfeng.com/data/files/pupebusurekexid.pdfIn PDF document text
    • https://a-pointpro.com/cms/ckfinder/userfiles/files/nitejenulim.pdfIn PDF document text
    • https://tort-art.ru/userfiles/file/nubomipasokomilov.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/3a017b422871a3a93f59c132fa1703a3/50361768901.pdfIn PDF document text
    • https://confetti-seasons.ru/upload/files/40905498734.pdfIn PDF document text
    • https://drinkpoint.com/uploads/files/38733896234.pdfIn PDF document text
    • http://quatangsongvan.com/hinhanh_fckeditor/file/84390245270.pdfIn PDF document text
    • http://cellesekorea.com/ckupload/files/ganukuf.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/91467413716.pdfIn PDF document text
    • http://etyekilovarda.hu/userfiles/file/27326773143.pdfIn PDF document text
    • http://daeryuhealthcare.com/ckupload/files/buxovolus.pdfIn PDF document text
    • https://supportsystemsvainc.com/home/ssvi/public_html/ckfinder/userfiles/files/wurotilepe.pdfIn PDF document text
    • http://cs-web-design.de/ablage/userfiles/files/19170545059.pdfIn PDF document text
    • https://okazdedziecko.pl/_files/Media/file/73469735720.pdfIn PDF document text
    • http://szjwwj.com/userfiles/file///76058297072.pdfIn PDF document text
    • http://okeefesreef.com/ckfinder/userfiles/files/51049145748.pdfIn PDF document text
    • http://tai-yang.tw/taiyang/upload/file/fusenibe.pdfIn PDF document text
    • http://stefani.cz/fck/file/77048203865.pdfIn PDF document text
    • https://ud-hobby.com/images/Upload/file/bivuwisigidepo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=promo+codes+for+robux+heroPDF 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_off0000decf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDECF 10580 bytes
SHA-256: 081251288dbff81b1ee44a0e5d17a3142be2d735f9ffab35d95ca6c46cb1b4b8
font_01_sfnt_off0000f6fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F10 18488 bytes
SHA-256: afe46c7a43b9af45db35f8c7d1a24f3fc4fb8756e0f67dc315abe6201056a99a