Malicious PDF — malware analysis report

Static analysis result for SHA-256 880f4d13eace76f0…

MALICIOUS

PDF

83.0 KB Created: 2021-03-23 22:25:20 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 2129b05334b06d8c91ef2d52d63fee3b SHA-1: da69fa82ee42c1f848b08451a0f828bc41a9f79d SHA-256: 880f4d13eace76f043216aea820ae5a80916d772e64f6e9bec403c087e77c0f9
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with one specifically pointing to 'bologen.ru/strik'. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the PDF is part of a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or delivering a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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.
  • 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://bologen.ru/strik?utm_term=preterite+vs+imperfect+practice+with+answers PDF link annotation
    • http://fulifubajamo.mywebcommunity.org/bare_faced_messiah.pdfIn PDF document text
    • http://gomakugagazeg.iblogger.org/36436695945.pdfIn PDF document text
    • http://nituzovido.getenjoyment.net/sentence_correction_gmat_preparation_guide.pdfIn PDF document text
    • http://marketop.club/jusomeponecnbj.pdfIn PDF document text
    • http://fefikaniki.22web.org/insert_calendar_in_excel_spreadsheet.pdfIn PDF document text
    • http://gedirobidepud.scienceontheweb.net/lirapepenutavorefelajev.pdfIn PDF document text
    • http://bajuzupur.22web.org/fisezizujizawubod.pdfIn PDF document text
    • http://bravos-kids.ru/ias_interview_question_answer_in_hindi1zvzz.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://144c9d4d-401b-437b-b89f-6a5816d7da47.filesusr.com/ugd/cd33f5_46deeb1a3b904cb08ce502dbd4c8e4cc.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6196782e-cf18-4b18-9827-03627358b06e/jugexatozubuxisofe.pdfIn PDF document text
    • http://pusuvolaxoxifun.rf.gd/57767996540.pdfIn PDF document text
    • https://9f9bd9fa-00fe-4673-b34e-9a629881f524.filesusr.com/ugd/09273f_15531ccc790b4c22a1f9261fd5399ab5.pdf?index=trueIn PDF document text
    • http://bukufam.epizy.com/nikikeg.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bf42b3c5-a52e-40fb-baeb-f5da7addc385/how_to_make_a_workbench_out_of_wood_pallets.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f767f6bf-c1f9-4ccc-8d61-f31a3a1b7c96/merchant_of_venice_full_text_with_line_numbers.pdfIn PDF document text
    • https://7aff118d-26f6-4d76-9bc9-1838009e7274.filesusr.com/ugd/f80014_338fe63095c14d5d96d7cba644e5a5ef.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/2e41985a-aef2-490d-9d2a-2651597fad8c/what_are_the_types_of_satellite_communication.pdfIn PDF document text
    • https://5c90cfa9-af55-48e2-9430-1f3580382729.filesusr.com/ugd/e2b09b_4d6574c0e74748959c9e30d15dd4e17e.pdf?index=trueIn PDF document text
    • https://b993c520-4fc9-488d-8dda-35d8b3dc2713.filesusr.com/ugd/6f5492_5c5b997183e14a6cacd7da82d077b51a.pdf?index=trueIn PDF document text
    • https://1b6fbac1-9b66-4609-9151-81f5d4c316f7.filesusr.com/ugd/5e81b9_b8d7928001dc4d4c84b6929ab3efbda7.pdf?index=trueIn PDF document text
    • https://e432c3f7-acc0-403b-bc7f-1b8c16782643.filesusr.com/ugd/6a4899_cd0a0c686dcd4132a965e8efe1496c0b.pdf?index=trueIn 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
    • 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_off0000ed88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED88 5376 bytes
SHA-256: 64e3ee18f75e1612687fc52669a90e85f6f82c3e86b67974477c0c99bc289e01
font_01_sfnt_off0000ffba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFBA 11824 bytes
SHA-256: e699fdf49e2eeedf5c8a45640c33273f51d60f552b74ee926d8b7f53d8b4d464
font_02_sfnt_off00012696.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12696 16352 bytes
SHA-256: a235935b7da1a3e0dfb4386fa22d70075346861adeac55da3f8f322ddd140fe5