Malicious PDF — malware analysis report

Static analysis result for SHA-256 f76c75557a9df97f…

MALICIOUS

PDF

81.7 KB Created: 2021-09-22 11:17:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 86d57f8795a7135936c9cbb298984b52 SHA-1: 6ec7121f853be9e945d5fbeda484328653fd0359 SHA-256: f76c75557a9df97fc0abc7f87d78ff1995782afcb545e44babda5912c28328b9
126 Risk Score

Malware Insights

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

The PDF contains a high number of embedded external URIs, many of which are hosted on disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous links point towards an attempt to lead the user to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://synerhu.ru/uplcv?utm_term=picsart+apk+file+download PDF link annotation
    • https://drddvichitra.com/userfiles/file/43331184780.pdfIn PDF document text
    • https://www.uflo.edu.ar/ckfinder/archivos/documentos/49657531641.pdfIn PDF document text
    • https://volandovia.it/public/fileeditor/file/24590270190.pdfIn PDF document text
    • http://galaxyjewel.cn/uploadfile/files/89353197914.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138d45314db0---pukatukudewuvetopedusilon.pdfIn PDF document text
    • https://astefin.ro/ckfinder/userfiles/files/79413350585.pdfIn PDF document text
    • http://protectakoteasia.com/ckfinder/userfiles/files/lajevabigobiwodadasiti.pdfIn PDF document text
    • https://rubenferro.com/userfiles/file/15910070697.pdfIn PDF document text
    • http://fosterfreezesantarosa.com/uploads/files/22544555571.pdfIn PDF document text
    • https://www.clinicaepilepsia.cl/ckfinder/userfiles/files/15652461884.pdfIn PDF document text
    • https://kodcomputers.ro/2664/uploads/tarasinubopojamajem.pdfIn PDF document text
    • https://youxsoft.com/uploads/files/fusufimidunebiwajavod.pdfIn PDF document text
    • http://flex-link.cn/uploadfiles/files/julanezeb.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16140ab7a00b17---27129420733.pdfIn PDF document text
    • http://gruppocaminiti.it/userfiles/files/lavurefuruta.pdfIn PDF document text
    • https://ostrichtours.com/ckfinder/userfiles/files/33076837919.pdfIn PDF document text
    • https://lesura.net/userfiles/file/86166648545.pdfIn PDF document text
    • http://t-eamplus.de/web/editor/files/73648680250.pdfIn PDF document text
    • https://kaxtongroup.com/home5/maxconne/public_html/kaxtongroup/assets/images/newspostimages/files/defiwesazoxopabarafunoraz.pdfIn PDF document text
    • http://erodiertechnik-wenzel.de/userfiles/file/sefibasezusiwopezaporiruk.pdfIn PDF document text
    • http://filtrydokoparek.pl/img/all/keselawojumegiwe.pdfIn PDF document text
    • http://joesservicecenternj.com/userfiles/files/24745289632.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_off0000daf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF2 17792 bytes
SHA-256: 1f58d5dcf8e859298150ab3cbf179716b1aee9c15b3dbf1aaa8153139665708f
font_01_sfnt_off000108c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108C6 10792 bytes
SHA-256: 1f1918c6a62d0cee9eaaa4d0bb7252928f1245e9b8c6a838d3c10463185d8f4c
font_02_sfnt_off000121d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121D9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1