Malicious PDF — malware analysis report

Static analysis result for SHA-256 951773f6d03088a5…

MALICIOUS

PDF

83.2 KB Created: 2021-09-20 07:21:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 43b781bb7630e322f165ba1be8b05a0c SHA-1: 74b4976204f4e4aaa6481411ed2c08e0f852535a SHA-256: 951773f6d03088a5fa08f9c07b11325a3c3e56a6a72dce232c45a30ee60c9494
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. The presence of a 'download button' heuristic and numerous links to PDF files on distinct hosts suggests a link farm designed to trick users into downloading a secondary payload. While no scripts were explicitly extracted, the nature of the PDF and the associated heuristics point towards exploitation for client execution, likely involving JavaScript to facilitate the download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://kovacsoltvaskerites.hu/images/file/bedixugoze.pdf In PDF document text
    • http://tfforming.ru/d/files/golevekimipubag.pdfIn PDF document text
    • http://atreve.eu/ubezpiecz/obrazy/file/42426188588.pdfIn PDF document text
    • https://wodepcb.cn/uploadfiles/files/43776549356.pdfIn PDF document text
    • http://yevres.fr/ckfinder/userfiles/files/niviposelewuja.pdfIn PDF document text
    • http://dj-venci.com/uploads/pages/files/paxuvepiverabowiduz.pdfIn PDF document text
    • https://www.zochrot.org/ckfinder/userfiles/files/46020714045.pdfIn PDF document text
    • https://www.ksmt.edu.np/assets/ckfinder/userfiles/files/54990100378.pdfIn PDF document text
    • https://yam-token.com/business_school/uploads/file/90175860621.pdfIn PDF document text
    • https://arichaindia.com/userfiles/file/77848354406.pdfIn PDF document text
    • http://cestovni-postylka.eu/userfiles/file/zosawi.pdfIn PDF document text
    • http://zuche0551.com/upload/file/35605503416.pdfIn PDF document text
    • http://premiercontainerlines.com/media/ftp/file/xizelutuwusaxovomodo.pdfIn PDF document text
    • http://electric-kernbichler.at/53727953120.pdfIn PDF document text
    • http://benetalent.com/upload/files/85654077033.pdfIn PDF document text
    • https://ymvii.com/admin/upload/files/jujekatusorewuxelazura.pdfIn PDF document text
    • https://icoachyou.biz/images/ckeditor/files/xexuzivamevariwufebuser.pdfIn PDF document text
    • https://qualitygums.com/userfiles/file/devugusubabo.pdfIn PDF document text
    • http://maivietnamesecotati.com/uploads/files/40367634231.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/nemutab.pdfIn PDF document text
    • https://villanakarin.com/userfiles/files/bowudusagowetuloz.pdfIn PDF document text
    • https://marthomaktrplrdiocese.org/ckfinder/userfiles/files/turagede.pdfIn PDF document text
    • http://enjoybowlramenandpoke.com/uploads/files/fujinedelagole.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161343a61aa43c---bozuzojabaw.pdfIn PDF document text
    • https://petribax.nl/userfiles/file/36709532132.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161381cda44d60---1767190756.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=aplikasi+android+untuk+pc+paling+ringanPDF 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_off0000e198.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE198 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f9aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9AA 17204 bytes
SHA-256: 4159752065c7ce13788352407ea33c8075ddff3fbbe2442a2e6024fb6bc63ea3
font_02_sfnt_off0001265b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1265B 10728 bytes
SHA-256: d0caa23d776a729930fa3f16baac89f582d916a1ee1f522fc2f289c36f6b50d5