Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8c56b35a5a65cde…

MALICIOUS

PDF

73.6 KB Created: 2021-09-07 22:02:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: eccd3209c244cece2e52b3ffa9ca4723 SHA-1: 21d672b18726fc7d75bfdcca57b04b514f50b265 SHA-256: b8c56b35a5a65cde7ba3673bc5954e7521962c71dfe8602d8bf7cedb6fce841c
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to potentially compromised websites, suggesting a link farm designed to redirect users. The PDF structure and embedded URLs point towards a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://vetportonaccio.it/userfiles/files/difunesixusifax.pdf In PDF document text
    • https://kuepancong.com/contents//files/goxagagarafafudonosawu.pdfIn PDF document text
    • https://aarushimukhwas.idealviews.com/userfiles/files/11036995596.pdfIn PDF document text
    • https://kermoulin.com/userfiles/file/xovinovewasaluluxu.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/5b5e55c6b10b853c14b65220a401afaf/22745711436.pdfIn PDF document text
    • http://zxsolar.com/d/files/melibabo.pdfIn PDF document text
    • https://mashtalkandil.com/userfiles/file/30451385828.pdfIn PDF document text
    • http://fatamorgana.fr/uploads/assets/file/35450237558.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160acad9e90e86---27177754663.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0b3182a4e---zetowitunodozo.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/48466959288.pdfIn PDF document text
    • http://daeryuhealthcare.com/ckupload/files/98066641878.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b12be4ebf02---68271707940.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/gimumixipe.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/32146715451.pdfIn PDF document text
    • http://mimarkamilozkartal.com/userfiles/files/56386907519.pdfIn PDF document text
    • https://vieclamday.com/userfiles/file/tusitatitupilipam.pdfIn PDF document text
    • https://yocarbroker.com/upload/ckfinder/files/31072928672.pdfIn PDF document text
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/mvtj4n3tkjjgqm8d1s9oh5lv6p/56025524929.pdfIn PDF document text
    • http://isystem.hu/ckfinder/userfiles/files/22655825789.pdfIn PDF document text
    • https://binarbaidtrading.com/public_html/userfiles/file/xeviwulat.pdfIn PDF document text
    • https://al-farh-iq.com/upload/userfiles/file/43154985425.pdfIn PDF document text
    • http://acrclubinversores.com/files/galeria/files/26270496760.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/7479a8e3e5526caa72aca12d7877928a/doliredaduwuxasafe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=ielts+reading+academic+pdf+2018PDF 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_off0000bd7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD7D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d58f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD58F 15992 bytes
SHA-256: 29afaa6c864d50becf8cc6f867a82014d604b2b197de4a97379765b653b565cb
font_02_sfnt_off0000fe42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE42 11296 bytes
SHA-256: d0db993e3ec0ec3858e823622844adee5832a31a0f3ebb115c16eb5e0d011941