Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd2624e25f9e6bcf…

MALICIOUS

PDF

82.5 KB Created: 2021-09-14 10:32:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: bb4a9f429ce818c42709e3317f81e447 SHA-1: 67008dc17d35a25ef0188181df970543eacb4e9c SHA-256: fd2624e25f9e6bcf96fd1d6a5d2ff4e794c18f4664c88a075d6c177a07bd4932
126 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it's a link farm designed to redirect users. The embedded URLs and the PDF's structure suggest it's part of a phishing or malware distribution scheme, likely using a lure related to 'thirteen reasons why pdf free download'. No scripts were extracted, but the PDF structure and numerous external links point towards a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://tdsns.ru/userfiles/file/wumuvewiwusopu.pdf In PDF document text
    • http://controldellaves.com/app/webroot/arxius/file/bapugepofuvebifek.pdfIn PDF document text
    • http://studiovalentini.eu/userfiles/files/povor.pdfIn PDF document text
    • http://beveragesgs.com/userfiles/file/tawixenakafiremulifep.pdfIn PDF document text
    • https://ipekyolumedya.com/resim_galeri/file/sulokuz.pdfIn PDF document text
    • http://liveisagenix.com/ckfinder/userfiles/files/70509442665.pdfIn PDF document text
    • https://cafesca.info/ckfinder/userfiles/files/domumefutotiga.pdfIn PDF document text
    • https://dailyiat.com/html_upload/file/zesafifobasi.pdfIn PDF document text
    • https://aspit.ro/imagini_ws/95897251477.pdfIn PDF document text
    • https://nestsearch.in/admin/uploads/file/xebeno.pdfIn PDF document text
    • http://mstreatmentadvances.com/userfiles/files/59635477294.pdfIn PDF document text
    • https://szelvedojavitasmiskolc.hu/files/files/1290977421.pdfIn PDF document text
    • http://dobermanncz.eu/files/65629690247.pdfIn PDF document text
    • http://lnyuanzong.com/uploads/files/20210904185208.pdfIn PDF document text
    • http://lawngo.net/fckfiles/61611178475.pdfIn PDF document text
    • http://moonlightmontessori.com/upload/files/kopilotafitivisitinudu.pdfIn PDF document text
    • https://searchkar.com/ci/userfiles/files/72005807805.pdfIn PDF document text
    • https://mundolibre.cl/uploads/userfiles/files/padifarewisel.pdfIn PDF document text
    • http://nhatrangpalacehotel.com/app/webroot/upload/files/gudabu.pdfIn PDF document text
    • http://binhchuachay.info/Images_upload/files/77436588194.pdfIn PDF document text
    • http://fornacedelia.it/userfiles/files/livapinobona.pdfIn PDF document text
    • https://printsolutions.printsolutions.bg/uploads/wysiwyg/files/delozodisi.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613e3c1a0a775---zelabeponevugarokuvafo.pdfIn PDF document text
    • http://starinviter.com/ckimagefiles/585612776.pdfIn PDF document text
    • http://cuboni.com/uploadfile/hong202109061142599806.pdfIn PDF document text
    • https://smobiil.eu/userfiles/files/zedet.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=thirteen+reasons+why+pdf+free+downloadPDF 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_off0000dd35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD35 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f54c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF54C 10760 bytes
SHA-256: 9aa00a61fa5521b5db0b4a21a577e746e832f7d7c97629029546b50c9346b771
font_02_sfnt_off00010e0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E0D 17732 bytes
SHA-256: a5e127d25c44510b91d15918a61a321020946ab558a722529973f46bad7958b2