Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8c07bfd0b4e48ee…

MALICIOUS

PDF

70.1 KB Created: 2021-09-28 04:53:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: bb7645895d37060af9414ed986a9bb3f SHA-1: baf2a025a86c09ef33ae4c00c8a6b945cb439a75 SHA-256: b8c07bfd0b4e48eea522f997b550480cccc63910f0b4a6ccb1d9da35829a61c3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm with numerous URLs pointing to other PDF documents, a common tactic for phishing or malware distribution. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM and ML_NYX_PDF_MALICIOUS firings strongly indicate malicious intent. While no scripts were explicitly extracted, the structure and embedded URLs suggest the document is designed to lead the user to a malicious download or phishing page.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://quatden.vn/webroot/img/files/jadevirekaxafozu.pdf In PDF document text
    • https://syteq-pro.com/userfiles/file/polomatizesunu.pdfIn PDF document text
    • https://0a3exp.com/upfiles/editor/files/87784827010.pdfIn PDF document text
    • https://stpm-sa.com/userfiles/file/37304100760.pdfIn PDF document text
    • https://luckysurface.itweald.com/uploads/files/6144b8ecd21ef.pdfIn PDF document text
    • http://pokebarslo.com/uploads/files/44357302969.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/161314a98cb09b---26689316491.pdfIn PDF document text
    • https://saikekanglun.com/filespath/files/20210905065351.pdfIn PDF document text
    • https://organicfertilizerproduction.com/d/files/1188697665.pdfIn PDF document text
    • https://get-insurance.in/ckfinder/userfiles/files/7591787889.pdfIn PDF document text
    • https://autopits-directo.migrupoq.com/ckfinder/userfiles/files/36644760826.pdfIn PDF document text
    • https://www.blondel-bois.fr/ckfinder/userfiles/files/22988697978.pdfIn PDF document text
    • https://melz-feu.ru/upload/dikisenibejisojixovukuj.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/27543715384.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613bcdb811992---pujoj.pdfIn PDF document text
    • http://www.oe.com.tw/ezadmin/ckfinder/userfiles/files/nefojipenoxunepaxed.pdfIn PDF document text
    • http://okmarin.ru/userfiles/file/fodapasegizepelijog.pdfIn PDF document text
    • http://mygiftltd.com/userfiles/file/bobokozezedevukiwodosibi.pdfIn PDF document text
    • https://iskoruma.com/upload/ckfinder/files/zuxufumuturalatenina.pdfIn PDF document text
    • https://shreegroupco.com/userfiles/file/35543077468.pdfIn PDF document text
    • http://aimic.com/userfiles/file/12995718459.pdfIn PDF document text
    • https://pottoka.info/files/galeria/files/manilufu.pdfIn PDF document text
    • https://intekcanada.com/ckfinder/userfiles/files/majivokozaxawuwubovadik.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=download+groovepad+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_off0000b231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB231 15992 bytes
SHA-256: 95377045c94e1ce72c7a817f17e58a8a1eaf7fcd510e7278437336b0af64159a
font_01_sfnt_off0000db11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB11 10452 bytes
SHA-256: 0d26c8a2e66a4735d70b8328c7a163d2de881b679f16b065bed41c26d126e093
font_02_sfnt_off0000f2bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1