Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7b9c2e03498bb9e…

MALICIOUS

PDF

86.7 KB Created: 2021-06-11 18:48:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 9c90288346ff957b20a3948cd35610f6 SHA-1: bdc875c65681a813a1b93e33e2bb3e1a1fcf922f SHA-256: b7b9c2e03498bb9e0b1ee789eb1ab748226d73350a5b61c2589cf773c91bbe22
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm for phishing or malware distribution. The document body, though heavily obfuscated, contains references to 'Resident evil 4 hd patch' and the authoring application 'wkhtmltopdf', indicating a lure to download potentially malicious content. ClamAV detection and ML classification strongly indicate malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://crysiq.ru/uplcv?utm_term=resident+evil+4+hd+patch PDF link annotation
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/7db2d3237e77ac251b199eecc426266e/doterob.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160b14eb8d8624---57437077197.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/ism0f1l5knce3shjtpfmksj6ch/sitozijigufife.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160bd122b26e84---jafemolawizo.pdfIn PDF document text
    • https://tavio.ru/files/file/gademobaxuvemod.pdfIn PDF document text
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/34c40vtat8ie3lnrjdfet5hn5d/36342645331.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609273e6b1f46---ruwulin.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/5m924rrmrge8i29k3id824h2p2/55768677539.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16076b1ddf0862---57076123991.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/944c271c436cb8197b12dc3ac8382363/pivipiwaboposipulavupux.pdfIn PDF document text
    • http://mbcasc.net/imgs/file/26223972968.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/96jne77qj9t01n0i0qtmgasvtk/zazorenese.pdfIn PDF document text
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/b859ee003fe4bbae75da5bce61596839/37527173700.pdfIn PDF document text
    • https://patriciobanados.cl/upload/file/In PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608150a8b5025---21044104763.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/nagareweko.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/manovunodoman.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000111f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111F6 5220 bytes
SHA-256: 3e3b27f9fc4c7befcd52c94c68b83fe5fcb26a26d1b42650ca3d1f249aa07998
font_01_sfnt_off000123c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123C5 13996 bytes
SHA-256: 60e38fdaf75e717b41a7d3de92e2f0e2a83eed18f06f3ef3a318543082ab6b47