Malicious PDF — malware analysis report

Static analysis result for SHA-256 237fd8740a0a0e8d…

MALICIOUS

PDF

71.1 KB Created: 2021-04-29 20:25:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: a4821f4f4e56dc930e783a9e07df34d7 SHA-1: 4f968a2734e7b02c67b92d7cb3a401efebc74751 SHA-256: 237fd8740a0a0e8dad670cda5f2af0ce579b57907b85954fe59143e4029eb7a1
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised websites, suggesting a phishing or malware distribution scheme. The PDF structure and embedded links are consistent with a link farm attack, designed to redirect users to potentially harmful content.

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 http://www.pilonidalsinus.gen.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f18538555c---wigipuxazasofemigubaloxe.pdf In PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607c7f16dbc9e---sadixa.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160838ac8a7e4b---95323087468.pdfIn PDF document text
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/02180fde5fe28c7bbaf3044014f7fd93/dejamotofikipotojikusawo.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607185e3f0af0---97849126158.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/9e5cuqhj6js06hocijtjrfhc80/bujodazesadexabezu.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/dac52c7c4d16762bc730c88c7f94629c/nebifefoga.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/160891cb6ed9e4---68166792715.pdfIn PDF document text
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ede8c5ecab---75247427426.pdfIn PDF document text
    • https://sandzak.best/wp-content/plugins/super-forms/uploads/php/files/a0c814d1a1d6f13176f5ac77510858c7/1474062525.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/b3e6ded6893f3a71156bd638033d7f45/91930092270.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f08d53bd75---sipogusi.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/5991fbf733139ebb9cfc6c9675f9e01f/53371854784.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1d3fb2fb0---71578003171.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/e8cb9741087e34d6230f41cc30bec9bb/60543975398.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/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=from+genes+to+genomes+hartwell+pdfPDF 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_off0000d9eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9EB 5500 bytes
SHA-256: eea03629f5eac18893ff0fca13cb210acb116139febb44e14bc818b61c003bf5
font_01_sfnt_off0000ec93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC93 10112 bytes
SHA-256: 05f62b2e98798b12fdc5f20386fc6d1ba97721b74c23bc93d8318a41392a9e37