Malicious PDF — malware analysis report

Static analysis result for SHA-256 b73e768ed00b24f5…

MALICIOUS

PDF

69.1 KB Created: 2021-06-10 21:35:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 21fb692a50df06a3949d7b862e8ae9aa SHA-1: 9408e6ef65b046a7907642f60cdedf4ddbed871d SHA-256: b73e768ed00b24f50be475e567444b92b19eb204d006fe966e6813a7ee64f8ce
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a phishing or trojan threat. It contains numerous external URIs and embedded links pointing to compromised WordPress upload directories and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, but the presence of external links and the high confidence verdict strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://nomylo.ru/uplcv?utm_term=hazmat+quiz+answers
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/6359597f48cc72c1245242a0a9bb2814/38270681537.pdf
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/a80527fe13b5b8bddf908847380cacf6/59407023775.pdf
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b41f8a21def---lenupadasegawopefovese.pdf
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c001ab1e8cd---66426364731.pdf
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b74cd15e9c4---tebab.pdf
    • http://www.awakohchang.com/image/upload/File/exijerolov.pdf
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/44339dd97d514322259d47b10997d9d4/91908614711.pdf
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607e814f4ba87---82885187298.pdf
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/0eead9c30e02e449c79d80dcacf5498a/selenit.pdf
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084cc30e472e---nagexixiza.pdf
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/718998aaa57c47af5e9a1d39745011b5/fasubexifef.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/39quv848cjs3vhhd9isr73rt0c/94696750642.pdf
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/1609b87e1c25f4---javaloludi.pdf
    • https://seataclighting.com/wp-content/plugins/super-forms/uploads/php/files/535f6201f85b7af6022d1abd537a995a/budojutimibobixuwi.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d321.bin
735d4f33fb4951649e63bfb08d8ad8f36a0eb1537edefd87983c1ed46bdc7344
pdf-font-stream PDF embedded font (sfnt) at offset 0xD321 5028 bytes
font_01_sfnt_off0000e43c.bin
28cc0bf79c86a219929fab98cf90fdf216be23d1229fdb9be108567b0dbb88ec
pdf-font-stream PDF embedded font (sfnt) at offset 0xE43C 10560 bytes