Malicious PDF — malware analysis report

Static analysis result for SHA-256 c28f7e680f219e4a…

MALICIOUS

PDF

77.5 KB Created: 2021-09-16 01:51:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: ca0469482456e6977117c13796507221 SHA-1: cca72cdb15dc0f40e886b828ea7bdb5b5c56c6bc SHA-256: c28f7e680f219e4a576b030745e5dc187e9aa9632a2fd1ca6c9279784077d4cc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://zapatosperezcabrera.com/ckfinder/userfiles/files/giges.pdf In PDF document text
    • http://piotrkowska77.pl/zdjeciafile/15088767715.pdfIn PDF document text
    • http://vesimport.ru/userfiles/file/dugudonikusegagukefavul.pdfIn PDF document text
    • http://phannhan.vn/files/usersfiles/files/pijukovikig.pdfIn PDF document text
    • http://stellarp.com/userfiles/file/45535446436.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133b59212cdc---zigobakuvolizaji.pdfIn PDF document text
    • http://movitecnic.com/ressource/site-image/files/96554592350.pdfIn PDF document text
    • http://nickelsgrafikdesign.de/ckfinder/userfiles/files/voxamivis.pdfIn PDF document text
    • http://vetranhtuong.info/luutru/files/35251840429.pdfIn PDF document text
    • https://sedefartphotography.com/resimler/files/3760301271.pdfIn PDF document text
    • https://chrmglobal.com/userfiles/file/gujitamewadinuvejuwubega.pdfIn PDF document text
    • https://sanghvicranes.com/staging/media/10229394088.pdfIn PDF document text
    • http://odnoklassniki-files.ru/images/uploads/files/20715960688.pdfIn PDF document text
    • http://purofirstli.net/userfiles/file/1020058041.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/1rcoh3dhdavk4e0n9adn88fg5b/bumemun.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/161369b3b2488c---zavupukagowe.pdfIn PDF document text
    • https://terracetemayonetim.com/upload/ckfinder/files/zagamo.pdfIn PDF document text
    • http://homeloanz.net/images/e/file/nutemewawonar.pdfIn PDF document text
    • https://matrixx.lu/images/dewaxajofisabukaxafemixup.pdfIn PDF document text
    • https://kltccompany.com/ckfinder/userfiles/files/21252046273.pdfIn PDF document text
    • http://madiagranitosilano.it/userfiles/files/9784060018.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ffdd2cf810---gepixek.pdfIn PDF document text
    • http://dreiseengrundschule.de/files/6428621494.pdfIn PDF document text
    • http://thienanglass.vn/upload/files/zizefolunosisajik.pdfIn PDF document text
    • http://bolshunoff.ru/images/wysiwyg/file/65096375776.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=3+way+video+call+androidPDF 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_off0000ccba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCBA 17096 bytes
SHA-256: f5d058e3ad33e26b79f5a283f22c291b19277651124beb33209fa52ec8f6e6df
font_01_sfnt_off0000f8ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8ED 10436 bytes
SHA-256: 4d71813d58e0baa58b0c66d47b6ed7cafd9fb32d8e7e8ea0dcd89f0a14d3311b
font_02_sfnt_off000110ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1