Malicious PDF — malware analysis report

Static analysis result for SHA-256 41166af1001b7f80…

MALICIOUS

PDF

77.4 KB Created: 2021-04-22 12:02:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 2dcc32494bd3c4a1ed950058cc7f008c SHA-1: 4179082e1124eafdc692b11876d2c8ca6f840781 SHA-256: 41166af1001b7f809097e5b2b195d59687493a1b5516faf3d34fe0650407fbef
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, many of which point to unknown or potentially malicious domains, suggesting a link farm or phishing attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a phishing lure designed to redirect users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.a1touchsolution.nl/sites/default/files/43963154407.pdf In PDF document text
    • https://www.afscme65.org/system/files/webform/tikat.pdfIn PDF document text
    • https://natsihwa.org.au/sites/default/files/webform/46250275999.pdfIn PDF document text
    • https://web.liderpapel.com/sites/default/files/webform/wavunivuzabanovomid.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/5308316073.pdfIn PDF document text
    • https://extranet.blanchisserie-toulousaine-de-sante.com/sites/extranet.blanchisserie-toulousaine-de-sante.com/files/documents/justificatifs/goxara.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/memirudomonejusowanasu.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/mimixinaxeralowevowijut.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/zasadavatemomafupe.pdfIn PDF document text
    • https://www.blplegal.com/sites/default/files/webform/3097059720.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/veser.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/povufukawonafano.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=what+is+the+starting+salary+of+mba+marketing+in+indiaPDF link annotation
    • https://minorsoncampus.princeton.edu/system/files/webform/tuvoluxasivawujunaz.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/gegisikirusesikogibo.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/58023923203.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE3D 5640 bytes
SHA-256: aae87b6acbd7317e20e526dd8648573f11642830b725fa0718b1b7d5363a0dd4
font_01_sfnt_off00010152.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10152 11508 bytes
SHA-256: ca7ed9bf3a026e76587f9e7ec1f250c4c530b27074d92e3524e73d8c552c9a0b