Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f3efbb3c498e3d6…

MALICIOUS

PDF

83.2 KB Created: 2021-07-02 12:38:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: b7b29d9b93ced2dbe21340b97302fc34 SHA-1: 56b4f8c6177fe05f2c75e11ad4bec694b327b973 SHA-256: 0f3efbb3c498e3d66fa928b1a6c319226d1975d3a4e47b80a0207d2b8305cbd4
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://forumhrdbekasi.com/webroot/userfiles/files/dugusezezepa.pdf In PDF document text
    • https://ta-taiwan.com/app/webroot/userfiles/files/23001993449.pdfIn PDF document text
    • https://fourseasons.events/wp-content/plugins/super-forms/uploads/php/files/cb8f7f4f9d4a9f0e90e6c2e5a383d105/kasezelinosekodogamedu.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/5cf6de2a290558af85866568ac331477/64696930743.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c8d6c18ed77---jakukifob.pdfIn PDF document text
    • https://airflow-skateboards.com/upload/file/46298519027.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160784dcb2fb7f---86330686592.pdfIn PDF document text
    • https://trimix.bg/UserFiles/File/91735311514.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609d7030bf179---2009079559.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/mamabisesineset.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a12d2de33b9---49252716676.pdfIn PDF document text
    • http://kovacsoltvaskerites.hu/images/file/wemoti.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/nusalevokemam.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16092b897cc7de---jugemilewe.pdfIn PDF document text
    • http://christschoolblr.in/userfiles/file/vulegaduzusuwinoz.pdfIn PDF document text
    • http://bayanairag.com/uploads/userfiles/files/fukubajurumekovajuri.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/gfirfctfkpmpthifkfr8eufitq/padasudov.pdfIn PDF document text
    • https://xn--80aaa1arbfjoe3bzh.xn--p1ai/data/files/parevi.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbd7f6bdcc---91537929632.pdfIn PDF document text
    • http://jakebenmd.com/clients/0/0e/0eef9d569b11303d075d19626cc6f958/File/19834417410.pdfIn PDF document text
    • http://consulcongress.it/uploads/assets/file/68686170722.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/12rq61fuh8jsv63rq7qdjlq3up/judesiwagapaxuzusasefev.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/44rclmv0hm6i4mphm7pdadeic3/56989351694.pdfIn PDF document text
    • https://stef-nancy.fr/upload/document/7457212888.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/7746e47e73b8982b74cab90bb386b8ae/vofezefodenegonurabakuzi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=chest+pain+and+feeling+shakyPDF 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_off0000e004.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE004 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f81b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF81B 10792 bytes
SHA-256: 1b7d41d787cce49e6248c63a90db8594d41e5b6bc7f1aa812dc54cecf77a5966
font_02_sfnt_off000110bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110BF 18544 bytes
SHA-256: 1c4841805067f9fab39c71d91155ac077e21df63b58f0c51949f0e9f2804ba3d