Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb9e47c85ae2a663…

MALICIOUS

PDF

83.1 KB Created: 2021-10-13 05:52:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 0bdab5a112fcfebaa8312d9072d7b343 SHA-1: f5a970d8b67d9988ddc6c9bacb2b2e2c2c59e631 SHA-256: fb9e47c85ae2a66346368fdc9ad9e6ecf9b5275157ab74e4c473e537983c05d3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate this PDF is malicious. The PDF contains numerous embedded URLs, many pointing to disposable domains, and one heuristic specifically identifies it as a link farm. While no scripts were directly extracted, the presence of embedded URLs and the nature of the heuristics suggest a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 http://mathrainbow.com/userfiles/file/zimoxa.pdf In PDF document text
    • http://geonatlife.es/ckfinder/userfiles/files/kubanil.pdfIn PDF document text
    • https://bharatiyabhashaparishad.org/ckfinder/userfiles/files/56255671026.pdfIn PDF document text
    • https://selispin.com/calisma2/files/uploads/vezivexakaletazugidoj.pdfIn PDF document text
    • http://eikenhorstgroep.nl/userfiles/file/zelinudezud.pdfIn PDF document text
    • https://estoniapools.com/contents/files/xudumovufedapoze.pdfIn PDF document text
    • http://hotelbasantresidency.com/uploads/jafijeluguzos.pdfIn PDF document text
    • http://pekingtogo.com/uploads/files/mopuputoposogavufowibi.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/16156f6025bec4---miperefomexisetu.pdfIn PDF document text
    • http://weiddy.com/uploads/files/202109072038488520.pdfIn PDF document text
    • http://auburn-companies.com/userfiles/files/kusuwupevekamomukoteduta.pdfIn PDF document text
    • https://sikahaiphong.com/images/news/files/tufilig.pdfIn PDF document text
    • http://thekkadyinfo.com/userfiles/file/50271023616.pdfIn PDF document text
    • https://www.gullyracing.it/admin/ckfinder/userfiles/files/teruwafobosobe.pdfIn PDF document text
    • https://kvzriu.org/images/file/95436873733.pdfIn PDF document text
    • http://tokyosushilohaus.com/uploads/files/nenonuxamuranugefidebo.pdfIn PDF document text
    • http://sin-hua.org/userfiles/natola.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/da89de266978e7d36fc7d73bea51373e/73266805541.pdfIn PDF document text
    • https://zilalcooling.com/other_files/File/15521698419.pdfIn PDF document text
    • https://sofupingame.com/calisma2/files/uploads/89306164948.pdfIn PDF document text
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/zogafegulubuludanofulomut.pdfIn PDF document text
    • https://zarrue.com/app/media/images_description/files/47893544175.pdfIn PDF document text
    • http://pronobile.com/catalog/file/14568307276.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/D9plVHj2VOU/uplcv?utm_term=assistant+general+manager+cover+letterPDF 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_off0000df4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF4D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f75f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF75F 18160 bytes
SHA-256: 788f329299bce1435b18295704494ef2e748e31eee730f951cd62bdacd99e9c8
font_02_sfnt_off0001268e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1268E 10620 bytes
SHA-256: 528741edb2fac3e615303851258dcb05317612363c70f6c8f9b28723fb74b169