Malicious PDF — malware analysis report

Static analysis result for SHA-256 957778848abcff5c…

MALICIOUS

PDF

82.7 KB Created: 2021-09-18 22:13:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bab7ced3303fc549500429b2ccb091d3 SHA-1: 08e07b71776a5dded4562e28700a87cce4f45ba2 SHA-256: 957778848abcff5c5e7962cc148f7ca43bf2348724e30a2adafd5fa2b5065a49
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of embedded JavaScript and a large number of external links, many pointing to PDF files on potentially disposable domains, suggests a phishing or malware distribution scheme. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further supports this, indicating the PDF is used to host many links on low-reputation domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://tekartltd.com/upload/files/nifelimenujona.pdf In PDF document text
    • http://www.ciesol.com/ckfinder/userfiles/files/38627607249.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/40546064267.pdfIn PDF document text
    • http://eqletstalk.com/uploads/files/202109121709373968.pdfIn PDF document text
    • https://fivetc.vn/uploads/files/jifuluxivagivur.pdfIn PDF document text
    • http://dichvutheapec.com/upload/FCK/file/85463211568.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613582e970b8b---ramapagaruvuxepupepupoliv.pdfIn PDF document text
    • https://pikhospital.com/ck_uploads/uploads/files/6229708565.pdfIn PDF document text
    • http://grandinhr.eu/images/user/file/58376360091.pdfIn PDF document text
    • http://hcstonetw.com/uploads/files/202109150647049788.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/rizawifigilenikesimifekus.pdfIn PDF document text
    • https://itracmediav5.com/ckfinder/userfiles/files/20398240576.pdfIn PDF document text
    • http://cuacuonnhaxuongbinhduong.com/upload/files/37481333620.pdfIn PDF document text
    • http://alompar.hu/uploads/content_files/files/41377062345.pdfIn PDF document text
    • http://noticiascgnews.com.br/ckfinder/userfiles/files/gumuwebepefarikozuwemaxu.pdfIn PDF document text
    • https://alpinebadmintonacademy.com/ckfinder/userfiles/files/woxuwasawesugijig.pdfIn PDF document text
    • http://www.louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/5328566043.pdfIn PDF document text
    • http://machi-tomo.xyz/js/ckfinder/userfiles/files/8566616589.pdfIn PDF document text
    • http://sun-eko.eu/files/file/xebezadimesabas.pdfIn PDF document text
    • http://dentalweek.eu/userfiles/files/22995731089.pdfIn PDF document text
    • http://gestioniarmatoriali.it/25815573986.pdfIn PDF document text
    • https://elnativocoffee.com/silver/upload/files/76134892905.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16133582991bb2---bebij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=rent+chal+mera+putt+2PDF link annotation
    • http://cluster006.ovh.net/~greeters/namur/ckfinder/userfiles/files/lirajobusiwub.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_off0000dc9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC9B 18700 bytes
SHA-256: 3c64162ce357003ac465c97eec7c3fd5e3376f1cceff638f52930cdce93c276e
font_01_sfnt_off00010dee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DEE 10524 bytes
SHA-256: d0ceb46e5468be552e131bea6537028595ad3ed283f3a5cf1daa87eb8df2f002
font_02_sfnt_off000125ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1