Malicious PDF — malware analysis report

Static analysis result for SHA-256 c03bd71fa90ddd25…

MALICIOUS

PDF

86.7 KB Created: 2021-07-16 12:41:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: cfd515e1d7130bbefbb6e0f6025cff5c SHA-1: e9759ecd939deda433dea69909304c891c00ce8a SHA-256: c03bd71fa90ddd250ef42d9271e275c0671c1756327c54f6927fcd7e630386af
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ClamAV and an ML classifier, with multiple heuristics indicating it functions as a link farm. The PDF contains numerous links pointing to compromised WordPress sites and other disposable hosting, suggesting an attempt to distribute malicious content or phish users. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific user lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/mgch39vn9uqqbjh1rgojkj3jkr/jenokupelolujosuvajo.pdf In PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607cdc8a38844---kamimenumanukide.pdfIn PDF document text
    • http://itineraire-consulting.com/ckfinder/userfiles/files/12864737650.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609a0b6a9de56---50517658832.pdfIn PDF document text
    • http://classicalgardenornaments.com/uplds/file/36786089789.pdfIn PDF document text
    • http://trevelci.ru/ckfinder/userfiles/files/wesomoj.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074a4661516c---rusogudopetaxo.pdfIn PDF document text
    • http://ceskylakros.cz/userfiles/file/88027120745.pdfIn PDF document text
    • https://sssmri.com/ckfinder/userfiles/files/56274459107.pdfIn PDF document text
    • http://casier-a-bouteilles.com/file/63816429234.pdfIn PDF document text
    • http://elitvorota.ru/f/file/83097907234.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ad4825d4e6---11828934466.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/a11f04f342a884e46df7262fce3a2221/sibinofu.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/2j9u8247o7507pqej82aud3s72/wazunarosigug.pdfIn PDF document text
    • http://ahchala.com/img/file/2304283363.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d072f7728cb---gobekadipuxajuxijamafup.pdfIn PDF document text
    • http://siripanyalamphun.com/user_img/files/xakenijam.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/c21c59e7b2b56d0f80a6e9fcfd612186/47907491287.pdfIn PDF document text
    • http://emailreceptionist.net/userfiles/file/jepirufaruredamufosuxitaj.pdfIn PDF document text
    • https://kompaspt1.com/contents//files/87712296416.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/imcg3j992dcpqfec50boro3f9v/58470531172.pdfIn PDF document text
    • http://abwmercury.com/uploads/files/4503768217.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/36142866486.pdfIn PDF document text
    • http://thesetnews.com/images/fckeditor/file/mapakamebejedam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=staph+aureus+urinary+tract+infectionPDF 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_off0000f1db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000109ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109ED 16524 bytes
SHA-256: bbafec893b2121b2c15aec7ff3c491f3fc2117cd0cdf686988820849f0eff037
font_02_sfnt_off000134c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134C0 10820 bytes
SHA-256: 3a97f5912cda0b046058fb7d9300f8581fa1bd90b81ebdf00207b96c2f0997d3