Malicious PDF — malware analysis report

Static analysis result for SHA-256 5471aab5409026f0…

MALICIOUS

PDF

92.8 KB Created: 2021-09-22 10:04:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: a3514ddb5038cd32d43152327925751b SHA-1: b16a14326014f6b00e467e1800bcbc9cb685db64 SHA-256: 5471aab5409026f06a477469f1aac4eb99184da29cac6e835b1f6f52222da73b
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many pointing to potentially disposable domains, suggesting a link farm or phishing lure. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior, indicating the PDF's purpose is to redirect users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://aradmissions.com/ci/userfiles/files/2259265503.pdf In PDF document text
    • http://www.gyndoktors.de/ckfinder/userfiles/files/48056106046.pdfIn PDF document text
    • http://theprojectmanagement.guru/cote_dor_import/admin/ckfinder/userfiles/files/85447956405.pdfIn PDF document text
    • http://decoworld.in/dayafter/uploadimages/newsimages/file/5108067452.pdfIn PDF document text
    • https://sledovani2.gpshlidac.cz/www/userfiles/files/xovege.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1613b896074ebb---dujomoxojibogixatutozuv.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/e5a25fc5f9e7e87fdb0f984ddf789e52/60998000904.pdfIn PDF document text
    • http://fsgzb.com/upfolder/e/files/20210919201808.pdfIn PDF document text
    • https://mycocoa.org/images/upload/files/noxasavasugeri.pdfIn PDF document text
    • https://dabanbep.tanglehadong.com/upload/files/35344875626.pdfIn PDF document text
    • http://lab4050.com/upload/editor/file/72650594415.pdfIn PDF document text
    • http://zbraneklapka.cz/ckfinder/userfiles/files/povizodidagulovuxil.pdfIn PDF document text
    • http://webinaris.eu/ckfinder/userfiles/publics/files/99018981412.pdfIn PDF document text
    • http://www.anapharmata.hu/ckfinder/core/connector/php/files/musisofitasa.pdfIn PDF document text
    • http://pretaporter-pegah.com/userfiles/file/15761148453.pdfIn PDF document text
    • http://szzxwx.com/Upload/Upload/file/202191864549741.pdfIn PDF document text
    • http://xn--80aejmo0alc.xn--p1ai/ckfinder/userfiles/files/rifeviba.pdfIn PDF document text
    • http://chuaphucluong.com/uploads/image/files/94319874285.pdfIn PDF document text
    • http://wienbildarchiv.com/upload_files/files/95920211580.pdfIn PDF document text
    • https://pgp-puh.hr/fck_media/file/kepivarajogubelamu.pdfIn PDF document text
    • https://wfbulgaria.com/uploads/wysiwyg/files/90021536489.pdfIn PDF document text
    • http://net-marketing.hu/images/files/sebulekawesovesaxavuz.pdfIn PDF document text
    • http://svazekobciorlice.cz/userfiles/file/60651136772.pdfIn PDF document text
    • https://mp2020.csysadmin.com/ckfinder/userfiles/files/ralolusapexelusax.pdfIn PDF document text
    • https://2ruoteexpo.it/ckfinder/userfiles/files/filaz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=dead+space+martyr+pdfPDF 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_off00010a3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A3E 17152 bytes
SHA-256: 6ec6959b264bfc425bc47635e1c9797ab5cc4f0f1ef7fd1849b2b3a15dc2f389
font_01_sfnt_off00013598.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13598 10536 bytes
SHA-256: e1fad1352d23e16c7adb3b290dbdf7a63005cb1c501770878beda73f641c7de6
font_02_sfnt_off00014dac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14DAC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1