Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d9d2f779ec2e715…

MALICIOUS

PDF

76.7 KB Created: 2021-04-14 09:12:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 5cffba7ef9fd62c4ae198fbeb7d6c551 SHA-1: 1b3616e1c03e4adadb172b53402c1bcd847ce0e2 SHA-256: 4d9d2f779ec2e7155e590240e393f3f2e5cea8724f7ab22daeb807ad783dee82
226 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing attempt. The 'SE_FAKE_CAPTCHA' heuristic indicates the document presents a fake CAPTCHA to lure users into clicking links. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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://jacksth.ru/strik?utm_term=oster+duraceramic+double+flip+waffle+maker+instructions PDF link annotation
    • http://likujodofefa.22web.org/claudinho_e_buchecha.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4414851/normal_60086fea6d131.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454968/normal_601dd1d7b1bb6.pdfIn PDF document text
    • https://cdn.sqhk.co/vagizabibo/ciaiiij/48380596224.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4378856/normal_5feb94fe646e7.pdfIn PDF document text
    • https://satizivuzaked.weebly.com/uploads/1/3/4/3/134383512/nedazanaged.pdfIn PDF document text
    • https://vuxidozeni.weebly.com/uploads/1/3/4/6/134669409/gogojen.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457572/normal_604b04f266276.pdfIn PDF document text
    • https://cdn.sqhk.co/jawutuwek/WQELLsd/bikozonigugegoku.pdfIn PDF document text
    • https://lefexaro.weebly.com/uploads/1/3/5/3/135324439/2354a022838e.pdfIn PDF document text
    • https://zupevojug.weebly.com/uploads/1/3/0/7/130740492/furujekize.pdfIn PDF document text
    • https://megewesaj.weebly.com/uploads/1/3/0/7/130738707/2a14b6103ec46.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/da3d1c04-22b2-472d-969e-b8855267d7ef/644321672.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5838371e-c959-45dc-9e3f-5b99ef6b0f55/zotulib.pdfIn PDF document text
    • https://5e73d190-47a4-4ead-99bf-7e9069f06a16.filesusr.com/ugd/55cc32_cc18f269e0784a988db5b0957016ed81.pdf?index=trueIn PDF document text
    • http://xadaxaxug.epizy.com/wumonerovusunimuk.pdfIn PDF document text
    • http://vaxotofeguzika.rf.gd/22816647959.pdfIn PDF document text
    • https://3d7c42e8-cad9-4196-8f3c-0f210fd97588.filesusr.com/ugd/1b7c00_6892f2dc6b90422db18e41b8d483e9eb.pdf?index=trueIn PDF document text
    • http://sujimivotabis.rf.gd/what_are_the_best_books_for_13_year_olds.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9d85bfd4-991c-454c-881e-b22f92080e90/chapter_17_the_progressive_era_vocab.pdfIn PDF document text
    • https://8b2103c5-345b-48fd-98e3-f19c90c4efd0.filesusr.com/ugd/0e2875_66dcf558ad1c4d45bc0cd3c73d0f28c7.pdf?index=trueIn 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_off0000ea43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA43 5624 bytes
SHA-256: 6cc9e50c48ead16d327f694f57d2c20635f3fec7ab9f186851527600b52f082a
font_01_sfnt_off0000fd56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD56 11576 bytes
SHA-256: 3cb5ab49db71455e023842d9e111ff6f3e3765978de977f90c744f8a46cc723d