Malicious PDF — malware analysis report

Static analysis result for SHA-256 3269958d714d0b8b…

MALICIOUS

PDF

76.4 KB Created: 2021-05-22 07:46:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: fbad470ea6d30de8c214def6c31b0f12 SHA-1: c8fe336442834b351e98e7cf9219690708823527 SHA-256: 3269958d714d0b8b9b9d0f8dfa07f018be851c46f897c472708dcc5dbc70de74
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

This PDF document is designed as a lure, using a seemingly innocuous title about replacing brake dust shields to trick users into clicking a link. The primary link, 'https://jacksth.ru/strik?utm_term=how+to+replace+brake+dust+shield', redirects to a potentially malicious site, indicated by the 'PDF_SEO_LINK_FARM' and 'PDF_SEO_UTM_REDIRECTOR_LINK' heuristics. The presence of numerous external PDF links suggests a link farm or phishing operation, and the ML classifier strongly flags this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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 contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://jacksth.ru/strik?utm_term=how+to+replace+brake+dust+shield PDF link annotation
    • https://xedowekogo.weebly.com/uploads/1/3/4/6/134609622/8a1914fec.pdfIn PDF document text
    • https://xufudigu.weebly.com/uploads/1/3/4/5/134515134/bomijatugur.pdfIn PDF document text
    • https://xaxafojub.weebly.com/uploads/1/3/0/7/130738676/a8bbee1bb7.pdfIn PDF document text
    • https://wezenazuzive.weebly.com/uploads/1/3/4/7/134764498/bebebudas.pdfIn PDF document text
    • https://wilepojaxuxag.weebly.com/uploads/1/3/4/6/134682450/folato-rewuta-tawuwup.pdfIn PDF document text
    • https://fexalikinuzumow.weebly.com/uploads/1/3/5/3/135324316/2e1d9.pdfIn PDF document text
    • https://zajodufukotu.weebly.com/uploads/1/3/1/8/131857357/4007638.pdfIn PDF document text
    • https://womagojewe.weebly.com/uploads/1/3/5/9/135961056/2840634.pdfIn PDF document text
    • https://budorezaru.weebly.com/uploads/1/3/4/8/134859022/muvowejokil.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/muxegeza/68755673836.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cef62ee1-eb14-4f14-9654-112c9ea49cd8/xepozajo.pdfIn PDF document text
    • https://s3.amazonaws.com/jivagajamav/amman_songs_ringtones_free.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d8fdef94-8059-4a2e-8e0e-d506e649f07b/harry_potter_books_ranked_no_spoilers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3873af1a-75b6-44d1-a87a-f115c8da0c5e/wubudenu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/535cd683-2b2c-4f60-857c-325115a0562f/10337648371.pdfIn PDF document text
    • https://s3.amazonaws.com/wegemebufojafak/how_many_partners_does_the_average_woman_have.pdfIn PDF document text
    • https://s3.amazonaws.com/zinudipir/rebatosorupusatar.pdfIn PDF document text
    • https://s3.amazonaws.com/taturi/how_much_does_it_cost_to_make_something_with_a_3d_printer.pdfIn PDF document text
    • https://s3.amazonaws.com/rujimidujek/56459004152.pdfIn PDF document text
    • https://s3.amazonaws.com/kotenu/89521805068.pdfIn PDF document text
    • https://s3.amazonaws.com/fajujiju/what_was_the_economic_condition_of_france_before_the_revolution.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7e569ffa-c36e-49b0-a06f-f805e6c369e3/python_manual_free_download_for_windows.pdfIn PDF document text
    • https://s3.amazonaws.com/zuguvoxoki/coldest_province_in_canada_today.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_off0000ef69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF69 5416 bytes
SHA-256: 300688dd45c4c82f89c1b99193ba245fdbb922f247b84eedfa21e7c589022c76
font_01_sfnt_off000101d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101D2 10084 bytes
SHA-256: 86fa4f3c87b44bb93da0e7a40c06adf050e0695aef9d090c72116f722f8761f9