Malicious PDF — malware analysis report

Static analysis result for SHA-256 729740de72edae0a…

MALICIOUS

PDF

75.1 KB Created: 2021-06-22 16:26:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 40a968297f4e0e085e41036da1cbfe08 SHA-1: eb7338255fc3005a83c429ef7013f0dbafac0ebd SHA-256: 729740de72edae0a68aec2be603d322deb65ef73a62d880838a2f55f2d10e091
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm used for phishing or malware distribution. The document body, though heavily obfuscated, appears to be a lure related to 'tracer study of senior high school graduates'. No scripts were extracted from this sample, but the presence of multiple external links and the overall structure strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://amerismithenterprises.com/wp-content/plugins/super-forms/uploads/php/files/c56bb196f8d0fcb480c8c3da16957309/96351577791.pdf In PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/fb59658f383c274ac8b75fbce3a8e4be/81859861091.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/04mc9db2h05fs2db4lpuecnrr4/dutaxilofageker.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b666271d37d---levimefufa.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/bb755f7e347e92cf22bc8db72ddf682e/razoromawunabi.pdfIn PDF document text
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087fbac4db82---45504608626.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/883710b55244db4baf584f89fc5224c0/20003330665.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/644458411a8aaeae65d321c8d579e351/metogelopijotixe.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608fdf000431a---89204610037.pdfIn PDF document text
    • http://4bx.pl/public/file/majuvog.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/f365469df99c1f1dc37443b56a41d101/xojanisasitokaviw.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/f6616c7e27d4764209529d0c6497053e/sewagozixopago.pdfIn PDF document text
    • http://tsg-vaganovskoe.ru/ckfinder/userfiles/files/rifunowetafax.pdfIn PDF document text
    • https://noddy.nu/images/file/9779079829.pdfIn PDF document text
    • http://ateliergermain.net/sites/default/files/file/83718750798.pdfIn PDF document text
    • https://whiteelephant.co.in/wp-content/plugins/super-forms/uploads/php/files/63f1290873765e626fed5f21f3e9700d/fasunaserikadi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=tracer+study+of+senior+high+school+graduates+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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e5b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B3 5468 bytes
SHA-256: cfb0e31b9c51fe31555e613fbead905ee578f54a6cfff498d08f52e3da4578b4
font_01_sfnt_off0000f84e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF84E 11076 bytes
SHA-256: ca007dc2748a032bc2f065990b70781857048a9d3ddbeaa7590d929df3295ed1