Malicious PDF — malware analysis report

Static analysis result for SHA-256 398209bfb07dbadb…

MALICIOUS

PDF

76.4 KB Created: 2021-10-01 14:59:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 6d0770b9e5d6b5a245f88614f429d138 SHA-1: 54cdccc81b2a3a02f68b4963f3d7d9dd404835ba SHA-256: 398209bfb07dbadbb1ebb3743b1be468c78d322b5791434fb78aa7c40f419be5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as a malicious PDF by ML classifiers and ClamAV. It contains numerous embedded URLs, many of which point to PDF files on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for these links. While no scripts were explicitly extracted, the presence of external URIs and the overall structure strongly suggest a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://barrospizzadb.com/uploads/files/42975627817.pdf In PDF document text
    • https://bloomland.com/sites/bloomland.com/files/patobegovazomulimumo.pdfIn PDF document text
    • https://burkina-businessschool.com/business_school/uploads/file/mogedo.pdfIn PDF document text
    • https://sim2007.com/files/sodotanivo.pdfIn PDF document text
    • http://pallenberg-busreisen.de/uploads/files/18135413001.pdfIn PDF document text
    • https://satesayap.com/contents/files/dubapoxudinamufidewowaj.pdfIn PDF document text
    • http://espressobuilders.com/app/webroot/files/userfiles/files/xezekesegisutevulutazi.pdfIn PDF document text
    • http://gymostrov.eu/gymostrov/userfiles/file/ranorozavekisumuzo.pdfIn PDF document text
    • http://nikolalepojevic5.com/multimedia/file/jutosixokumefej.pdfIn PDF document text
    • http://taxplus.in/images/contentimages/files/kapofiniposaw.pdfIn PDF document text
    • http://ilovestory.com/upload/file/jedupogo.pdfIn PDF document text
    • https://coastalstudio.com/images/main/file/tegokalojimomofukogavaw.pdfIn PDF document text
    • http://fitviewer.com/files/file/nuxebefiwifadajal.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/b85b6rj9e8qmibnddl32m1nse1/topimanifozizoxijodut.pdfIn PDF document text
    • http://trumoi-khutrung.com/upload/files/51125363835.pdfIn PDF document text
    • http://adasbruiloften.nl/userfiles/file/20706086293.pdfIn PDF document text
    • https://zooiguana.pl/app/webroot/media/files/15968246212.pdfIn PDF document text
    • https://www.studioline.ie/ckfinder/userfiles/files/tonipinemalem.pdfIn PDF document text
    • http://autolubitel-irk.ru/userfiles/file/rajimuro.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137a70528b9b---44087869092.pdfIn PDF document text
    • http://climtech.com/files/files/salonudizililemol.pdfIn PDF document text
    • http://brno-skoleni.cz/ckfinder/userfiles/files/38922383190.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=harry+potter+deathly+hallows+putlockerPDF 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_off0000bd07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD07 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d51e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD51E 10800 bytes
SHA-256: 60d83f2be7d667b6058be116f8b4aa0bcfb45f17e4481366aa987e87da7d74cd
font_02_sfnt_off0000ee3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE3B 19428 bytes
SHA-256: c7ac14fb0ad9fb68a3d54a8d87e8ef9f142e99f101f3cc739f2e010a2b179473