Malicious PDF — malware analysis report

Static analysis result for SHA-256 50a66cfbc8ac8119…

MALICIOUS

PDF

83.0 KB Created: 2021-09-18 17:32:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 78e579d198f983e92810e2678f7b4d32 SHA-1: 4d7b36a861430e004c87b318024c9e05e493b420 SHA-256: 50a66cfbc8ac8119f0c9e28b70fc6c48a3d75bdf9beb73e4945cd6679f28b54d
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as a phishing trojan and ML classifiers indicated maliciousness. It contains a large number of embedded URLs, many pointing to unknown or potentially malicious domains, suggesting a link farm or phishing lure. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further supports this, indicating a tactic to obscure malicious destinations. No scripts were extracted, but the overall structure points to a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://educhina.mn/editor/files/janilit.pdf In PDF document text
    • http://mijinmotor.com/fckeditor/userfiles/file/vigiwi.pdfIn PDF document text
    • http://hotelbellevuepalermo.com/userfiles/files/75060126901.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/161382988c5084---tisojonaxipebinor.pdfIn PDF document text
    • http://snsi.jp/image/news_file/wigebukevamoniguk.pdfIn PDF document text
    • http://spamsmsgiare.com/media/ftp/file/60541753388.pdfIn PDF document text
    • http://shbaicun.com/userfiles/file/2021091004451673499.pdfIn PDF document text
    • https://oceanflowerhotel.com/uploads/image/files/72918195072.pdfIn PDF document text
    • http://profstil.az/userfiles/file/bofozulonure.pdfIn PDF document text
    • http://spain-ex.com/images/blog/file/29333413072.pdfIn PDF document text
    • https://macroedunet.com/userfiles/file/kelelopola.pdfIn PDF document text
    • http://vxclouds.com/userfiles/file/4883410454.pdfIn PDF document text
    • http://wych123.com/upload/files/mirojotijupatuxu.pdfIn PDF document text
    • http://ubytovani-budejovice.cz/picture/vtextu/file/79232482491.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/67779538854.pdfIn PDF document text
    • http://giovanniseneca.eu/userfiles/files/88736127083.pdfIn PDF document text
    • http://tvcsoltau.de/userfiles/file/gazazuvuben.pdfIn PDF document text
    • https://kingyao.com/uploadfiles/files/20210918_005447_9793.pdfIn PDF document text
    • http://air-con.ru/upload/files/37653407886.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/16134f97eabd4a---suxipusifaduwovejirudibej.pdfIn PDF document text
    • https://ev-owners.jp/userfiles/files/99625795344.pdfIn PDF document text
    • http://termosystem.pl/userfiles/file/rivutamosasulopilan.pdfIn PDF document text
    • http://forglory.cz/ckfinder/userfiles/files/xamukef.pdfIn PDF document text
    • http://inimtrento.it/userfiles/files/sinasatoduretemibuge.pdfIn PDF document text
    • http://otczenacts.com/media/files/mixasubulinubavufebiw.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/46486628570.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=too+hot+to+handle+season+2+watch+onlinePDF 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_off0000ddbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDBE 18556 bytes
SHA-256: d88efd9f779ce10ffe2f3bca1b1252aefc275f1415837910552a99ef8b89140f
font_01_sfnt_off00010db7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DB7 10536 bytes
SHA-256: a8d8fde457f0beb2ccb2c221532f241295b88a1a1bcd9c505dad0a4128fdc229
font_02_sfnt_off000125ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1