Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a4490508295ff8c…

MALICIOUS

PDF

74.7 KB Created: 2021-09-18 13:13:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: fdfe80f96095c48bec19e77228d658f9 SHA-1: 5ab4720940978b69ea50be7c8f6648df3ecd9527 SHA-256: 3a4490508295ff8cf8557cad86186edc5af3d25d851eb47b35f8338507ae4514
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many of which are embedded within the document body and point to disposable domains. Heuristics indicate this is a link farm, and ML classifiers and ClamAV strongly flag it as malicious. The presence of external URIs and the overall structure suggest a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://oniceh.ru/uplcv?utm_term=examen+exani+ii+pdf PDF link annotation
    • https://uleshuzatabc.hu/files/file/nokupad.pdfIn PDF document text
    • http://mnwebdesign.dk/userfiles/file/jobirebifipazaxofibin.pdfIn PDF document text
    • http://sfipl.in/userfiles/file/78971733508.pdfIn PDF document text
    • https://www.adoz.cz/ckfinder/userfiles/files/59238086179.pdfIn PDF document text
    • http://achwvs.love-mrt.com/upload/files/parelowim.pdfIn PDF document text
    • https://www.hotelrestaurantmacarena.fr/ckfinder/userfiles/files/tudabisopazosukob.pdfIn PDF document text
    • http://vitanova-cattery.com/upload/file/27455282961.pdfIn PDF document text
    • https://kingwaterpure.com/ckfinder/userfiles/files/79988211749.pdfIn PDF document text
    • https://lederstuehle-shop.de/ckfinder/userfiles/files/beponuxorabemijow.pdfIn PDF document text
    • https://ezgoe.com/10005001208290177/ckfinder/userfiles/files/feretesopumudub.pdfIn PDF document text
    • http://thermcom.cz/userfiles/file/25057324417.pdfIn PDF document text
    • http://arcstema.com/userfiles/files/rubudiko.pdfIn PDF document text
    • http://mineraux-et-lithotherapie.fr/ckeditor/upload/files/vojaxivimudibejomokadokoj.pdfIn PDF document text
    • https://computerzone.pk/file/84480930488.pdfIn PDF document text
    • http://chinasoftcore.com/userfiles/file///veradizoda.pdfIn PDF document text
    • http://cheumst.com/upload/fckeditor/file/94085402887.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613956663a3bb---diratad.pdfIn PDF document text
    • http://chithanhplastics.com/uploads/userfiles/file/nilulojitemirex.pdfIn PDF document text
    • http://diagcorlifescience.com/attachment/file/bazegigadupino.pdfIn PDF document text
    • https://pepinieramontana.ro/ckfinder/userfiles/files/2185902761.pdfIn PDF document text
    • http://joesservicecenternj.com/userfiles/files/vimozejovizobubeju.pdfIn PDF document text
    • http://jiendurancecoaching.com/ckfinder/userfiles/files/jopugalobatakepuwakunuxul.pdfIn PDF document text
    • http://www.tiendadelbordado.com/ckfinder/userfiles/files/2039309735.pdfIn PDF document text
    • https://sergiomauri.com/images/file/95867854371.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://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_off0000bf3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF3E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d750.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD750 18692 bytes
SHA-256: b6b6f13089ad3cb0fc29e976673df83aacfae1dfebe81481d85a340ecda21835
font_02_sfnt_off000106ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106EA 10212 bytes
SHA-256: 235374e458ebf3652469bd5e51d1d9034dfafe56c0047fa311ea14e97873e5ce