Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd9ab220b7cb4636…

MALICIOUS

PDF

74.4 KB Created: 2021-10-08 02:26:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 316b39055d56e31613634781050c213f SHA-1: 8a03bfd7366ba701654b4c4c4508c07966d1cb2c SHA-256: dd9ab220b7cb463662300a1693f3ca68f9dddc6df593196488cc355169c4882f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were directly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://queure.ru/uplcv?utm_term=top+bottom+meaning PDF link annotation
    • https://dulichduyendangvietnam.com/uploads/news_file/zomeguxexiz.pdfIn PDF document text
    • http://autoscuolavalerio.it/userfiles/files/6914046011.pdfIn PDF document text
    • https://vargyasnekonyveles.hu/kepek/other/file/maxetopuveniwisowiwapa.pdfIn PDF document text
    • http://acm-medicali.it/userfiles/files/11422967520.pdfIn PDF document text
    • https://groupunsur2.com/contents/files/53871782636.pdfIn PDF document text
    • http://ventensis.lt/public/ckfinder/userfiles/files/88030686288.pdfIn PDF document text
    • http://christ-china.com/filespath/files/20210907010357.pdfIn PDF document text
    • http://dieterheich.de/images/uploads/file/dawelesunogafesutarogup.pdfIn PDF document text
    • http://onlinetradeshow.ir/uploads/files/jozukidetiv.pdfIn PDF document text
    • http://www.poliklinika-hb.cz/userfiles/file/51544531961.pdfIn PDF document text
    • https://kolegium.inaheart.org/upload/files/5480262550.pdfIn PDF document text
    • https://www.esicm-old.org/admin/lib/ckfinder/userfiles/files/poxan.pdfIn PDF document text
    • http://daearesort.com/FileData/ckfinder/files/20210922_AD0B767DB68F1467.pdfIn PDF document text
    • https://aashianarealty.com/file/safalugipisurexekibi.pdfIn PDF document text
    • http://leebyenghun.com/new/upload/board/files/7385283708.pdfIn PDF document text
    • http://aotwresort.info/ckfinder/userfiles/files/27870510469.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/bfabbef833916328f67bddb31a3cef9a/69751571336.pdfIn PDF document text
    • http://leoclubmarsala.it/userfiles/files/pabozilaxatenudunovofiza.pdfIn PDF document text
    • http://versobrokers.eu/userfiles/files/52682843127.pdfIn PDF document text
    • https://matricula.arendic.cl/files/29284288897.pdfIn PDF document text
    • https://saigonservices.vn/images/uploads/files/2928521138.pdfIn PDF document text
    • http://relaxzenter.com/uploads/files/tudivevuvewep.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1615d40b837f90---gabul.pdfIn PDF document text
    • https://hsse.hssanesteban.cl/files/86207796150.pdfIn PDF document text
    • 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_off0000bf33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF33 17836 bytes
SHA-256: 322aa8336222205bacdd940b74b8441f58fb6ffdcaa00eada085120ade439af0
font_01_sfnt_off0000ed06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001051d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1051D 10384 bytes
SHA-256: 2be420fcf3073697002920083b718c937d385a741d47618c3d8963ba207fd7f9