Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfbcb675616a17e3…

MALICIOUS

PDF

71.7 KB Created: 2021-09-28 13:06:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-03
MD5: 6d5329ee10975f9467e32f08f499ab3a SHA-1: 006754de454f569affe2c09d26ccacf444f5ac74 SHA-256: cfbcb675616a17e3610d432a4892efcff67756c2c98de3a0797ec51f942f31f8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with a high heuristic score indicating it functions as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs point towards an attack pattern involving redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://thenext.pk/userfiles/files/mibipuruwomavejukimuke.pdf In PDF document text
    • http://yuhongzg.com/d/files/74778653517.pdfIn PDF document text
    • http://eurekaelearning.com/upload/news/file/27120322603.pdfIn PDF document text
    • http://indecomavo.pl/userimg/inc/58927240389.pdfIn PDF document text
    • http://ecoaga.com/documentos/file/81259271694.pdfIn PDF document text
    • http://lawyergz.net/uploadfile/files/dapebamivesurotarafi.pdfIn PDF document text
    • https://odlingfamily.com/userfiles/file/didelanosijefazanelojobi.pdfIn PDF document text
    • http://podiummoda.ru/userfiles/file/31374469882.pdfIn PDF document text
    • https://tour-paris-guide.com/cite_imgs/file/30996269047.pdfIn PDF document text
    • http://sva-jeanroze.com/xmedia/file/55835364919.pdfIn PDF document text
    • http://nhasachconggiao.com/luutru/files/puxegi.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/4327660757.pdfIn PDF document text
    • http://vkts.se/userfiles/file/67035475439.pdfIn PDF document text
    • http://sindikat777.ru/ckeditor/ckfinder/core/connector/php/uploads/files/42731321095.pdfIn PDF document text
    • https://educationindiajournal.org/ckfinder/userfiles/files/poroxemuje.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/25379011151.pdfIn PDF document text
    • http://stnicholasway.com/userfiles/file/kejimuwidanefuxov.pdfIn PDF document text
    • http://0228339500.kad.tw/kads/ckfinder/userfiles/files/xivubivibibi.pdfIn PDF document text
    • http://synergytaekwondo.com/click2buy_newp/userfiles/file/44168433279.pdfIn PDF document text
    • https://arch.ua/ckfinder/userfiles/files/sexen.pdfIn PDF document text
    • https://tigaintan.com/contents/files/rigozar.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/161495d0c0cef7---dajuvuginiran.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16151bf4485cb7---49821354574.pdfIn PDF document text
    • http://okna-stv.ru/userfiles/files/10615652145.pdfIn PDF document text
    • https://mut-zur-veraenderung-hambuch.de/userfiles/file/34851564127.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=among+us+cheats+mobile+androidPDF 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_off0000b214.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB214 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA26 17756 bytes
SHA-256: e95b8ff9292336114f5b217205a79b75da806dacbe6ba23b8aaada675080b9e1
font_02_sfnt_off0000f63a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF63A 11036 bytes
SHA-256: 5f23f83a1d1a7a17c0b492309f57efb1ffa9f8cf76325929a7bde6d773c62007