Malicious PDF — malware analysis report

Static analysis result for SHA-256 1810a7157de2ddcf…

MALICIOUS

PDF

85.6 KB Created: 2021-03-08 23:40:54 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: fc71483562252274d39c19926f4a58fe SHA-1: b4e22423a1b02c669969278de6e6c68b4b31e96c SHA-256: 1810a7157de2ddcfeb8b24e89cccac5c1360df2ab1adf0fc6b9797d234c068a1
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous external links, many pointing to PDFs hosted on disposable or user-generated content platforms, suggesting an attempt to manipulate search engine results or distribute further malicious content. The primary URL, https://jumiwimov.ru/wix?keyword=nyc+school+bus+fleet, appears to be a keyword-driven redirector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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 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.
  • 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://jumiwimov.ru/wix?keyword=nyc+school+bus+fleet PDF link annotation
    • http://getchambre.xyz/44046226559pq8vw.pdfIn PDF document text
    • http://albl.ru/mapusedida0s52q.pdfIn PDF document text
    • http://muldwych.com/nalawokigokepaf0n7hf.pdfIn PDF document text
    • http://rawoxaxevog.mygamesonline.org/44478933907.pdfIn PDF document text
    • http://reznitskygallery.com/29448036942xzos8.pdfIn PDF document text
    • http://xojuxelase.medianewsonline.com/pasuw.pdfIn PDF document text
    • http://luchdobro.site/the_summer_is_gone_film_2018bswvh.pdfIn PDF document text
    • http://veruvipavopa.getenjoyment.net/pioneer_elite_plasma_tv_will_not_turn_on.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://4541bc1c-e35c-4de3-bb44-1f53c3e1a56d.filesusr.com/ugd/68f66e_e4fa1e6a4f494550b003d71e9ea51703.pdf?index=trueIn PDF document text
    • https://27475d5a-2981-497d-8cd5-0c310ef10f8b.filesusr.com/ugd/9cb927_a51fe2d37d424e009f79457740ccba76.pdf?index=trueIn PDF document text
    • https://6bb2b61b-82bf-473b-8365-63ddb02ddbdd.filesusr.com/ugd/d55797_9fdb295ddc5440f38e0fc5653584927f.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f474f8d2-6489-4b98-b4f1-dd5036d17923/50313843647.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/df988557-24ef-44a0-9564-b2ac8c5067f9/5-2_skills_practice_medians_and_altitudes_of_triangles_answers_with_work.pdfIn PDF document text
    • https://s3.amazonaws.com/jixerubowi/fujalagupimulu.pdfIn PDF document text
    • https://7d6e376e-1ee3-4df5-88c1-8d1511d419f8.filesusr.com/ugd/7dd30d_7132567c0950487685d9bcddb9b36504.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/gekojulog/what_does_deviance_mean_in_psychology.pdfIn PDF document text
    • https://f770b3d7-c897-40e0-9323-5ad0abd91552.filesusr.com/ugd/1fa6dd_f84743e9ade34e30af0a1c2e8c0db342.pdf?index=trueIn PDF document text
    • http://samajusinifako.atwebpages.com/farajozetujodu.pdfIn PDF document text
    • https://68358877-4ee6-4e53-94f7-4bd9665c1f53.filesusr.com/ugd/3bbd68_d63ccd429484428a87aabaae3e009336.pdf?index=trueIn PDF document text
    • https://72b50e20-f79f-40ca-96b4-24bef83e308f.filesusr.com/ugd/1a1092_3b8bc8d9a2a540e2b7bba0b1137fcd05.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/390746b7-ad93-457e-816a-da2126acc98e/kopamagofojekafulirapobuj.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ee101f3-d026-48e0-865b-9f46f4ae6a74/15524650795.pdfIn PDF document text
    • https://s3.amazonaws.com/gixirojozogufux/noluno.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2e82b7b0-3d05-469b-8d91-f0c4f785843a/what_is_the_moral_of_the_story_why_mosquitoes_buzz_in_peoples_ears.pdfIn PDF document text
    • https://s3.amazonaws.com/tulosa/delray_beach_weather_report.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_off00011474.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11474 4872 bytes
SHA-256: de33306f9a5ae28b0685a1cfb7b2f373819607c33e6e0ab564407228380ed6c6
font_01_sfnt_off00012522.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12522 10520 bytes
SHA-256: ad7e0a2579c927071ee7ee63cf883360514105164fc0a36a9f9b32716b1f216d