Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a2371ebdf246a2f…

MALICIOUS

PDF

84.1 KB Created: 2021-09-08 19:50:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 026f50114b4667bc7edc7a47a03f94c1 SHA-1: 771b1b3daf801ac2276c396693e152aeaf42fb95 SHA-256: 4a2371ebdf246a2fd542442ade4f9117d139e9bfa06f593afc9cf13cde5f414f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous embedded URLs, with one heuristic specifically identifying a link farm on disposable hosting, suggesting a phishing or redirection scheme. The PDF structure and numerous external links point towards an attempt to direct the user to malicious external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.gesas.it/media/mailinglist/file/magas.pdf In PDF document text
    • https://nestsearch.in/admin/uploads/file/ludizodofemagazolatodav.pdfIn PDF document text
    • http://optometrystaprzemysl.pl/userfiles/file/lidubiwuvikabanipor.pdfIn PDF document text
    • https://ijtm.in/userfiles/file/57254267719.pdfIn PDF document text
    • https://thietbidiensino.vn/media/ftp/file/96799865608.pdfIn PDF document text
    • http://giorgimpianti.com/userfiles/file/26605837350.pdfIn PDF document text
    • http://grandviewgroupresort.com/upload/files/refilipamadideseroxa.pdfIn PDF document text
    • http://ez-surveying.com/htdocs/cljr/data/files/lifuxekivoboneziwebuto.pdfIn PDF document text
    • http://frangarcia.eu/upload/file/padogujo.pdfIn PDF document text
    • http://qiangka.com/ckfinder/userfiles/files/34752422432.pdfIn PDF document text
    • http://wskinbody.com/data/boardData/files/lejaxanusiwux.pdfIn PDF document text
    • https://kemxoithanhhang.vn/app/webroot/files/images/pages/files/51178755455.pdfIn PDF document text
    • https://sesconbs.org.br/ckfinder/userfiles/files/16932692455.pdfIn PDF document text
    • http://avvolodin.ru/upload/file/56923489936.pdfIn PDF document text
    • http://zeguvietnam.com/uploads/ckfinder/files/35670806772.pdfIn PDF document text
    • http://kientrucphatloc.com/upload/files/xumoredetej.pdfIn PDF document text
    • http://cnhhgj.com/upfiles/userfiles/file/jovatimakijigixegavojowo.pdfIn PDF document text
    • https://alaskaproauto.net/nbloom/fckuploads/file/88873799445.pdfIn PDF document text
    • http://dataction.org/demo/dataction/media/16550709154.pdfIn PDF document text
    • http://youzedu.com/ckimages/files/20210905095136488201.pdfIn PDF document text
    • https://comtraining.cl/userfiles/files/sixesi.pdfIn PDF document text
    • https://damiel.eu/userfiles/file/bilalajisab.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/16137d36ee0b84---96058110976.pdfIn PDF document text
    • https://www.grdr.org/paidel/ckfinder/userfiles/files/dojopenuzagivolezawexuxi.pdfIn PDF document text
    • http://uralinteh.com/uploads/files/38802141500.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=buffalo+wild+wings+nutrition+pdfPDF 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_off0000e4f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD0E 10780 bytes
SHA-256: 55b6fdb785fd075e7b87ec1cfdeec16eeb0f243945f2d5d6417892c2948e6306
font_02_sfnt_off000115d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115D5 17216 bytes
SHA-256: 650bb0559dd353aadf59843529f22244cb657e9d30499aded03e53167971cd81