Malicious PDF — malware analysis report

Static analysis result for SHA-256 c87253201826b7c6…

MALICIOUS

PDF

77.8 KB Created: 2021-05-26 03:18:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: eb6b56d7d01a839bb3bd8ffefff56318 SHA-1: b15accd6e8a1374c50c1af4a870b28bbe8b705a0 SHA-256: c87253201826b7c63d85d23625c72da94143eccd7ef437ae8e5922361b40dc9f
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised websites and disposable hosting, characteristic of a link farm used for SEO manipulation or to distribute further malicious content. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, and the presence of multiple PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics confirms the link farm behavior.

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://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/ef18a0557fe99102f07df0cb897478f3/13458540455.pdf In PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088716157d8a---lomefowiwogesikutepopu.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160743d758c385---77450851001.pdfIn PDF document text
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/d4a9f403c0cde33dae1d02e2cf382f46/44277111585.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/xakuzuwomubun.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160a612ce382cb---sosawigapemukogogodowukal.pdfIn PDF document text
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/c6665c35cd7559870128ce37c79626aa/wajon.pdfIn PDF document text
    • https://trellisdundee.com/wp-content/plugins/super-forms/uploads/php/files/4b4067713de8e8a819e40b889386e46b/48595378813.pdfIn PDF document text
    • https://bem-sa.com/img/file/lemasune.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160713cc43b85e---31448390510.pdfIn PDF document text
    • http://strahovka66.ru/userfiles/file/nutivolav.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16075280aa941a---8614341862.pdfIn PDF document text
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/lvqe813g4f67t4c137eq9rkqsr/zuretuxulilazudovatowi.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/16070ec6db1104---26964586798.pdfIn PDF document text
    • https://ols.lighting/wp-content/plugins/super-forms/uploads/php/files/0af5eba3536ee88996f3e94b0a4d8524/6823304153.pdfIn PDF document text
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/a79fc81bc96b126daefa1a83bc9fe3fd/7590282909.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=what+is+the+importance+of+hypothesis+testing+in+managerial+decision+makingPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ebfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBFC 5748 bytes
SHA-256: 6a5973b67790fac8e88499ae4fb8dc4c5c67637472d5a78e923222c92cda012f
font_01_sfnt_off0000ff75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF75 12328 bytes
SHA-256: d816c6b6f6b745f94e1e5928bf618746df7794dd6643097146eee4a86a83818f