Malicious PDF — malware analysis report

Static analysis result for SHA-256 b43b21c0000d433b…

MALICIOUS

PDF

77.9 KB Created: 2021-04-01 14:38:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 9351a05f628d1dfd78d5c66d1fcd8eff SHA-1: 15f4149a1c2d139b3dcb9cf371483ed69b2ac7e3 SHA-256: b43b21c0000d433b827f0a5fbf39634fc70ce288263b910ae748acb3642f8559
134 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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 https://nipisod.ru/wix?keyword=manual+of+freediving+bok PDF link annotation
    • http://kelijoninofi.22web.org/85433848882.pdfIn PDF document text
    • http://wspring.space/fosixojeranivarovaduxb06t3.pdfIn PDF document text
    • https://cdn.sqhk.co/kitujesijak/JJjdX1A/espn_magazine_cover_june_2019.pdfIn PDF document text
    • https://cdn.sqhk.co/kizafizutuw/jclDfja/telegram_app_download_link.pdfIn PDF document text
    • https://cdn.sqhk.co/kewudomavave/1u9jibq/72232499167.pdfIn PDF document text
    • http://moscowflowers.shop/55410911481qvgp7.pdfIn PDF document text
    • http://benaletuzulug.sportsontheweb.net/94546118974.pdfIn PDF document text
    • http://maxist.ru/trigonometry_formulas_list_for_class_10_downloadq1v4c.pdfIn PDF document text
    • http://bagesopabiwub.scienceontheweb.net/imran_alawiye_books.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://dexizijisub.atwebpages.com/budgeting_planning_and_control.pdfIn PDF document text
    • http://wififeju.atwebpages.com/10657711006.pdfIn PDF document text
    • http://gaxokumixopo.epizy.com/af_meritorious_service_medal_template.pdfIn PDF document text
    • http://vujapoguxesak.myartsonline.com/noun_worksheet_for_class_3rd.pdfIn PDF document text
    • http://joxumokuri.epizy.com/constitution_for_the_united_states_of_america_1746.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f286.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF286 5164 bytes
SHA-256: 1a749e5f657bdcb2c2d0f283e91adf6fb01b6b2738294ad092f1d57a6597f3f7
font_01_sfnt_off00010441.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10441 10972 bytes
SHA-256: bb1941915dd22bd1fc4b1d121fca8c80228c9b7aa115f4e0b93cc361ee3e48a5