Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd7b5b94df9be503…

MALICIOUS

PDF

85.2 KB Created: 2021-09-17 09:18:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: ed14d3f97e64ac5b7e9e0bf87e928e93 SHA-1: 799412b530dfd2e59b00af7ff280f4da8973c43c SHA-256: cd7b5b94df9be503a675f9ed93e66ebc3d3d6d652a17d7f1579c67bc6b604ce7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. The PDF contains numerous links to disposable domains, suggesting a link farm designed to obscure the ultimate destination. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://velapower.com/glwh/UploadFile/file/2021090404483273499.pdf In PDF document text
    • http://hmed.vn/upload/files/dojasizusuguxuwap.pdfIn PDF document text
    • http://aquarium-kochi.com/app/webroot/ckfinder/userfiles/files/58260110538.pdfIn PDF document text
    • https://komunalno.vrgorac.hr/files/lemigupo.pdfIn PDF document text
    • http://bekescsaba.varosom.hu/userfiles/files/nanakegapijuz.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd858dca3d---jadujujufa.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/lojilolav.pdfIn PDF document text
    • https://h1t-urlaurora1-turbo.com/contents/files/nivejabifapav.pdfIn PDF document text
    • http://yousefmaktabi.com/ckfinder/userfiles/files/80640635649.pdfIn PDF document text
    • https://gulfsupremesa.com/ckfinder/userfiles/files/20116232916.pdfIn PDF document text
    • https://cambodiadriverservice.com/userfiles/file/rizifuvejeresozejawepula.pdfIn PDF document text
    • http://ort168.com/upload/ckeditor/files/61583845085.pdfIn PDF document text
    • http://usateatop.com/_upload/files/lupesebirekekamotipaw.pdfIn PDF document text
    • http://margheritango.it/userfiles/file/mobulufeduxikeluketumaxo.pdfIn PDF document text
    • https://journeywithmypet.com/ckfinder/userfiles/files/8049736277.pdfIn PDF document text
    • http://slbreakingnews.com/ckfinder/userfiles/files/nawureruwepijar.pdfIn PDF document text
    • http://business-baltic.com/myfiles/dok/24934937251.pdfIn PDF document text
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/jogesepigumofobika.pdfIn PDF document text
    • http://pro-roubenky.cz/UserFiles/File/xobonuvututuriworo.pdfIn PDF document text
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/matuvinexevebokakakamom.pdfIn PDF document text
    • https://stephan-kratt.de/data/reiterhof/userfiles/file/22227970237.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/lolakanom.pdfIn PDF document text
    • http://patrick-vallot.com/upload/files/nusafom.pdfIn PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/55610500052.pdfIn PDF document text
    • http://autofox.lt/ckfinder/userfiles/files/pezudeninitimifodaje.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+organize+icons+on+android+phonePDF 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_off0000e7b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7B1 17832 bytes
SHA-256: c25bc8c5cf1a6e71c9dce5a48c9ab6bb35a51df1d4332194f4acfa5ceb50c5fa
font_01_sfnt_off00011639.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11639 10884 bytes
SHA-256: e93f1465ed2c1b914cd1f82d7373199c7355e6173109d354f4674a4145e5dfe6
font_02_sfnt_off00012f31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F31 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1