Malicious PDF — malware analysis report

Static analysis result for SHA-256 355b96255dbe5c92…

MALICIOUS

PDF

83.1 KB Created: 2021-06-20 20:21:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 44a7d698547df4e11ba040b5e25b65ac SHA-1: 4161067a73e59132a3cd7c73e4c8b81630020f29 SHA-256: 355b96255dbe5c9289cbbb53cfa04127367d8b147456a012cabce585fdbe06cf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm pointing to compromised WordPress upload storage. The embedded URLs, despite some being marked benign, contribute to the overall malicious intent by directing users to potentially harmful sites. No scripts were extracted, but the PDF structure and URL analysis strongly suggest a phishing or malware distribution lure.

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://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/c76961d63e579ab6a196b62f89793e0c/43011406015.pdf In PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/6a6c725c60266b8b87e01a41317540ad/63524135905.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/h62np85ct21h07bbvqavkp01e8/9122686935.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/533b1ff4d95f677259b9252426999ead/mokedugawubibetuz.pdfIn PDF document text
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/54df346abad2ae82aac360cbe5a2f010/43259833872.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/sankhc4ockhtlfkl8rtk1qbl4h/48213611283.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092f20dae32a---manirujer.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609b58aade7c1---gidimozane.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab58e867462---repatovawep.pdfIn PDF document text
    • http://personnelstrategies.net/userfiles/file/tavezakopixed.pdfIn PDF document text
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160b57b2b62c5e---natizakegenepejak.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/kgpei80kb34hbvo0i9mnpgq4j6/nulamewisiguxosodaj.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/esp7n00sni75m6emc3sl7717h4/37369292674.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/88718513715.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16094db0006b50---69844063820.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/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=summary+of+the+maze+runner+seriesPDF 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_off000106eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106EB 5232 bytes
SHA-256: 092fab77c7cecf9012ee42c6d57ad226954b0f0e1d838efd102342cd3a83dc93
font_01_sfnt_off0001189b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1189B 11444 bytes
SHA-256: af18c6ec21975c9c37526ffd7db77f70e1674d8cb24b4ae3fb23c4d2d857197e