Malicious PDF — malware analysis report

Static analysis result for SHA-256 2c64391da270f17e…

MALICIOUS

PDF

72.3 KB Created: 2021-04-20 15:44:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 8c2b99528b40034dec98cbad3c4a21e8 SHA-1: 4823000b59510ee976989e3176d015988d4c6a85 SHA-256: 2c64391da270f17e8b24de075273b9dd5dc2e1be5fdae21f24433f3b8aaf9060
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a high ML score and ClamAV detection. It contains numerous embedded URLs, many pointing to disposable domains, characteristic of a link farm used to obscure malicious destinations. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to redirect users to potentially harmful content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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.uts.cw/sites/default/files/webform/vogoledifekotukedadawen.pdf In PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/22559513310.pdfIn PDF document text
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/74543186253.pdfIn PDF document text
    • https://aboss.by/sites/default/files/webform/zivexovoburowunaxomenip.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/tekuxegejarikuferibo.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/xubapubawaral.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/22206840813.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/40041164747.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/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=used+stack+on+gun+safe+for+salePDF link annotation
    • https://printandmail.princeton.edu/system/files/webform/83401752781.pdfIn PDF document text
    • https://thesanfordschool.asu.edu/sites/default/files/webform/20850651402.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_off0000dc0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC0B 5244 bytes
SHA-256: 2645817e1cb86d9e8ed937f850fc8acaa04bb187f38064f15eb1ad7591a1013a
font_01_sfnt_off0000edfa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDFA 10856 bytes
SHA-256: 71393722c250c7590feb63e3ff398bc77cb71ecedc2343469c573b0dc2ec2223