Malicious PDF — malware analysis report

Static analysis result for SHA-256 328f7d3a8bef3cdf…

MALICIOUS

PDF

97.6 KB Created: 2021-06-28 00:38:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: dc669f31462528bdcfaa098088a528d8 SHA-1: 4bdb3e615d60e92925472718dff28dabbc47a5da SHA-256: 328f7d3a8bef3cdfe403631c8a18f880256e88a5aa51f49a232db95c42bf8c3b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised WordPress sites and disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of malicious activity, likely leveraging embedded JavaScript for redirection or exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/1606f27df2bbe7---jomoku.pdf In PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/vkj2n6ppvf9vai6bhrakfoguf9/83092164476.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/a9e55da9b70e25700b81260d316bd835/vonuvurepapexi.pdfIn PDF document text
    • https://www.varisistanbul.com/wp-content/plugins/formcraft/file-upload/server/content/files/160771fa9f094b---68959204801.pdfIn PDF document text
    • http://abwplazaview.com/uploads/files/bebuposimurepag.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c0e2fa05faa---91099718080.pdfIn PDF document text
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/7f7rqg4ir0po1n44hoha6lp5ma/60650442184.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/3814937380.pdfIn PDF document text
    • https://malashealthcare.com/userfiles/files/84857093366.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/4326b162f145536b2691477742e5c0a1/1158078502.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c1d21d4169---10586434299.pdfIn PDF document text
    • http://atmaircenter.com/lb/userfiles/files/pajotu.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a1ee3db6d52---dobijulugi.pdfIn PDF document text
    • http://pwr-tech.ru/userfiles/file/40100451919.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/8e7dbfe78d42b4dc218e453eb5652b1c/konasala.pdfIn PDF document text
    • https://mn-lawfirm.com/box/userfiles/file/darigunabavajakeguleganiw.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085f1a06bc64---45715957962.pdfIn PDF document text
    • https://tskrea.com/userfiles/file/gonubarubopulobijezixeva.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160ad92aa59d76---koxig.pdfIn PDF document text
    • http://handbook.hu/upload/page/file/gusovimefukolerexet.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f85b0c76f3---3498853403.pdfIn PDF document text
    • https://ndmoyun.com/calisma2/files/uploads/8448468865.pdfIn PDF document text
    • http://adveotec.com/img/file/52620856801.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=money+escheated+to+the+statePDF 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_off00011db6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DB6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000135cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135CD 10336 bytes
SHA-256: 850a7098216a0e5fd674236207521a79e36d63343ff6d296f83685881741d7a8
font_02_sfnt_off00014d20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D20 17080 bytes
SHA-256: fbc9d253f5db57903f1fb8a951c12d6c5f8b7951a11e01e89090580fb7093eb2