Malicious PDF — malware analysis report

Static analysis result for SHA-256 a378d41a59f0d7d6…

MALICIOUS

PDF

82.2 KB Created: 2021-09-22 13:20:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 71e58be00d688b07308d13409adeb612 SHA-1: 256003f7b3c080e3b5654564ea6c0167f7e7f655 SHA-256: a378d41a59f0d7d68b524845cca044c7dbc43a5c9ffdc73cc6bd21a23819beda
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to various domains, many of which appear to be part of a link farm designed to obscure the ultimate destination. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests a campaign focused on distributing malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 http://tamphuhiep.com/Images_upload/files/88922492343.pdf In PDF document text
    • http://www.sm.ac.th/ckfinder/userfiles/files/55348415572.pdfIn PDF document text
    • http://utuin.net/files/fckeditor/file/pamanupemotudu.pdfIn PDF document text
    • http://studiochiodo.eu/userfiles/files/sajizuvikewe.pdfIn PDF document text
    • http://kbidc.kr/upload/editor/file/1632160991.pdfIn PDF document text
    • https://afmiletisim.com/resimler/files/kemuwasasezakalazeta.pdfIn PDF document text
    • http://freehajjandumrah.com/admin/admin/uploadfiles/file/34614619478.pdfIn PDF document text
    • http://www.horakgolf.cz/ckfinder/userfiles/files/65692259263.pdfIn PDF document text
    • http://smartwealthhk.com/userfiles/97589366300.pdfIn PDF document text
    • https://smwebtechnology.com/arishayurveda.com/userfiles/file/26920976648.pdfIn PDF document text
    • http://angelojrobles.com/admin_initial_test/userfiles/file/74657554177.pdfIn PDF document text
    • http://xn----9sbbnbtte4cyg.xn--p1ai/ckfinder/userfiles/files/tusitamigisisa.pdfIn PDF document text
    • http://www.extramas.com/userfiles/files/13412186751.pdfIn PDF document text
    • https://nbtele.com/en/cache/fck_files/file/famomosotikoj.pdfIn PDF document text
    • https://ritascreation.com/userfiles/file/41229200066.pdfIn PDF document text
    • http://xn--80aa5alfu.kz/file/42583788172.pdfIn PDF document text
    • https://intrastorg.com/userfiles/file/22629733418.pdfIn PDF document text
    • https://sarna-zapiekanki.pl/ckfinder/userfiles/files/44046709697.pdfIn PDF document text
    • https://nk-sostanj.si/files/file/denojuxanatuk.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/1qneugeo35nepf0f1jak53vl9p/33011153034.pdfIn PDF document text
    • http://starcity-vinhomes.vn/app/webroot/img/files/surowowetodo.pdfIn PDF document text
    • http://mmckno2010.zkosuchdol.info/files/sotilozega.pdfIn PDF document text
    • https://lolakarimova.uz/ckfinder/userfiles/files/81502690896.pdfIn PDF document text
    • https://akconta.com/uploads/files/99825653029.pdfIn PDF document text
    • http://stowarzyszeniemalyksiaze.eu/img/upload/files/53965250644.pdfIn PDF document text
    • https://timminsrenovations.ca/file/vPxf9MSz32fR6bfA.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=how+to+copy+music+from+phone+to+sd+cardPDF 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_off0000dab2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAB2 11132 bytes
SHA-256: ff188941631ab02e76c98afae0cc61fcb7506d2d3eed4e9549af8b446e3eeee0
font_01_sfnt_off0000f483.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF483 17992 bytes
SHA-256: 547683c2a0967355b4e4bb56a460cfb6101abc9c8bb2de8407d5d0a6e196098b
font_02_sfnt_off00012325.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12325 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1