Malicious PDF — malware analysis report

Static analysis result for SHA-256 a524898ed5be9fc8…

MALICIOUS

PDF

81.2 KB Created: 2021-09-19 05:52:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4abc08f04fb2ad2625cc82f298b1f7ac SHA-1: fda0ca1fec4ec2fef2de28ac28ee0c7e2bb3cc8f SHA-256: a524898ed5be9fc80c8dff18d620575631ed7608e76acd96456578e002d6cfde
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing or trojan. It contains numerous embedded URLs that point to link farms hosted on disposable domains, suggesting an attempt to redirect users to malicious content. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further supports this, indicating the document's primary purpose is to host a large number of external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://wastran.ru/uplcv?utm_term=best+mp3+player+app PDF link annotation
    • http://www.sun-green.eu/ckfinder/userfiles/files/48265261044.pdfIn PDF document text
    • http://midesignvn.com/uploads/files/33932954563.pdfIn PDF document text
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/49564127527.pdfIn PDF document text
    • https://rawoctane.com/uploads/file/fonuzelegiw.pdfIn PDF document text
    • https://piataafacerilor.ro/app/webroot/files/userfiles/files/gajazifipefuwaxiranupuxi.pdfIn PDF document text
    • https://vatlieutaphu.com/upload/files/sizubufe.pdfIn PDF document text
    • http://umartravel.com/files/balosup.pdfIn PDF document text
    • http://miyisz.com/mingyi/images/userfiles/file/76786489333.pdfIn PDF document text
    • http://zjqzzx.com/uploadfile/file/2021091410373173499.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c190ebe5f6---miturilur.pdfIn PDF document text
    • https://www.la-providence-ehpad.fr/ckfinder/userfiles/files/73190085396.pdfIn PDF document text
    • https://kp-bs.ru/upload/files/36271993091.pdfIn PDF document text
    • http://lawyergz.net/uploadfile/files/261540888.pdfIn PDF document text
    • http://bangladeshceramicsociety.com/uploads/editor/files/85405344836.pdfIn PDF document text
    • http://tobn56.com/UpFiles/file/23390896537.pdfIn PDF document text
    • http://imhkayseri.com/resimler/files/sujijibuberur.pdfIn PDF document text
    • https://elitstroycraft.ru/source/file/40498068264.pdfIn PDF document text
    • http://primethailand.com/ckfinder/userfiles/files/67432080861.pdfIn PDF document text
    • http://ipmarketing.net/FCKeditor/editor/filemanager/connectors/userfiles/file/barelurewawosofo.pdfIn PDF document text
    • https://smilaxlabs.com/userfiles/files/44351299553.pdfIn PDF document text
    • http://liyangah.com/Upload/file/35573111599.pdfIn PDF document text
    • https://sensiblemachines.com/ckfinder/core/connector/php/files/51811471161.pdfIn PDF document text
    • http://www.roosprommenschenckelfoundation.nl/ckfinder/files/files/94790475462.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614654799478c---97041432767.pdfIn PDF document text
    • http://ctyrkolky-gamax.cz/data/dokumenty/75979002644.pdfIn 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://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_off0000daad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAAD 17468 bytes
SHA-256: 37fa8735300448d71e1d15ded4051f80b865ea5c460b5cd677108c48759e116b
font_01_sfnt_off00010781.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10781 10436 bytes
SHA-256: caf2cfe83be1a483f8ea03a06d3e3bd7b3b6265639813f3f3d7e77d3bcc1f65c
font_02_sfnt_off00011f4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F4B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1