Malicious PDF — malware analysis report

Static analysis result for SHA-256 c403f7bc576bd457…

MALICIOUS

PDF

82.4 KB Created: 2021-09-20 01:11:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 05ab9001c99088ce6123e3c3faf4293f SHA-1: 31fbcc8debc3252b686be8bc9e749f763a6bc1bd SHA-256: c403f7bc576bd45753f2d5fe8d1bf646a55e04bfcd39938d4a2c3b3c96a1ef0e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm on disposable hosting, with numerous embedded URLs pointing to potentially malicious content. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to external sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 5

  • 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.
  • 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://www.leasing.net.in/ckfinder/userfiles/files/2796205067.pdf In PDF document text
    • http://stigstudiotecnico.it/userfiles/files/20556464991.pdfIn PDF document text
    • http://demo-enriquemora.shopcloud.es/ckfinder/userfiles/files/41506779036.pdfIn PDF document text
    • http://ydyb.com/filespath/files/20210917154219.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/16138ee59bf302---nowajorokuburupafolux.pdfIn PDF document text
    • https://infrastone.com/userfiles/files/7331650009.pdfIn PDF document text
    • https://www.pension-chevaux-haras-gabereau.fr/ckfinder/userfiles/files/6822809692.pdfIn PDF document text
    • https://bcbc3399.com/upload/files/fibiwifedid.pdfIn PDF document text
    • http://theorientgarden.iorderfoods.com/uploads/files/24600567913.pdfIn PDF document text
    • http://nationshield.ae/userfiles/files/kumexepowalafona.pdfIn PDF document text
    • http://jingkangchem.com/upload/files/97152341484.pdfIn PDF document text
    • https://umartravel.com/files/wobefaxavukiv.pdfIn PDF document text
    • http://aquarium-kochi.com/app/webroot/ckfinder/userfiles/files/23842631474.pdfIn PDF document text
    • https://regenerateacademy.com/file/90152265501.pdfIn PDF document text
    • http://studioambienteterritorio.it/userfiles/files/naforawu.pdfIn PDF document text
    • https://ecotranslation.ca/upload/editor/file/fikuxixidenusinisivuwegal.pdfIn PDF document text
    • https://virtrade.gr/userfiles_lybo/file/96535193122.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/33344627407.pdfIn PDF document text
    • https://cahayamimpi1.com/contents/files/robos.pdfIn PDF document text
    • http://piemonteforyou.it/userfiles/file/zemuwufeni.pdfIn PDF document text
    • http://mgtuae.com/uploads/file/41607321257.pdfIn PDF document text
    • http://cavusofis.com/images_upload/files/xinigadok.pdfIn PDF document text
    • http://svazekobciorlice.cz/userfiles/file/virezolitipuvo.pdfIn PDF document text
    • http://weiken-rc.com/upload/files/fezapevedofanizosaj.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7e335603a---10395140611.pdfIn PDF document text
    • http://jia-longsofa.com/uploadpic/jialong151126/files/202109171351593534.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=something+that+starts+with+the+letter+nPDF 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_off0000db54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB54 18608 bytes
SHA-256: fb07eb0d046748ea9c291bfec604b7f16bee03b5f53efa2f4eb90562cd7a5491
font_01_sfnt_off00010b53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B53 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001236a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1236A 10716 bytes
SHA-256: 843f5c1f269e7fdd98e97590c6a7500535df892829588bf5fc23b9ca27d64a9f