Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3a75a0d576dd24f…

MALICIOUS

PDF

79.1 KB Created: 2021-04-12 23:37:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 60c88ebb2a7cc9fee2746bcbdf923137 SHA-1: 64c8de1bef3b7c80995174bf26ef00095fbef623 SHA-256: b3a75a0d576dd24f40cc0ee9872a0db65f26b99654d1ee9818ebc6a241351768
126 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate maliciousness. The PDF contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. While no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect the user to malicious sites, likely for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/tonitunivopevefasoxezaw.pdf In PDF document text
    • https://aboss.by/sites/default/files/webform/12404161593.pdfIn PDF document text
    • https://www.telluridescience.org/sites/default/files/tstc-applications/dadesiludidogujuta.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/fulakosilukubusovugatupus.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
    • http://www.pbttphtk.gov.my/sites/default/files/webform/32056102714.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/sidetarebuw.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/68406293253.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/27017481005.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/S30rS-6n6vg/uplcv?utm_term=blue+train+pdfPDF link annotation
    • https://printandmail.princeton.edu/system/files/webform/zupedofijemurak.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/nufimogunuzin.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/siwujomizawafoxewop.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/xegenaxug.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_off0000f8fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8FE 4908 bytes
SHA-256: f260dd80b66a29d71993e7c8d423317492106091de4cb5aff0452a9d064ec992
font_01_sfnt_off000109c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109C0 11332 bytes
SHA-256: 4167a6118e7d535e518039f742c470d553ce0de3e9b999fbf0893909525eb404