Malicious PDF — malware analysis report

Static analysis result for SHA-256 820c351a9751e617…

MALICIOUS

PDF

86.6 KB Created: 2021-03-14 18:44:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: c09c60612b521eadb58db411e798d3ea SHA-1: 5da3fdeb36fdfd1b9a9979551d6a0a3e5ee1d8ba SHA-256: 820c351a9751e617065aa6aaf20891d40c7a4971951cb4a21270ead0648df32d
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

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
  • 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.
  • 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://baarspo.ru/award?keyword=cae+speaking+test+sample+pdf PDF link annotation
    • http://zdorovienashevse.xyz/39555885153o1aor.pdfIn PDF document text
    • http://life50it.pro/constitucion_de_venezuela_1830_sistema_electoralvxptc.pdfIn PDF document text
    • https://mebuduwo.weebly.com/uploads/1/3/1/4/131453299/13492dcbc5846.pdfIn PDF document text
    • https://kaxorude.weebly.com/uploads/1/3/4/0/134095875/f99505937.pdfIn PDF document text
    • http://salearea.pro/no_oyes_ladrar_los_perros_analisis_literariot1pfl.pdfIn PDF document text
    • http://dupadevoz.22web.org/7173664436.pdfIn PDF document text
    • https://lifalaril.weebly.com/uploads/1/3/4/8/134883644/tofuz-girefowerebizeb.pdfIn PDF document text
    • https://sepanafawo.weebly.com/uploads/1/3/4/3/134316973/bogaserajakinud.pdfIn PDF document text
    • http://rilomenininun.getenjoyment.net/jovofoxuzegejodaketupubo.pdfIn PDF document text
    • https://zopamege.weebly.com/uploads/1/3/5/9/135966764/jixifobikulalilubi.pdfIn PDF document text
    • http://luxasireku.sportsontheweb.net/26658583831.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/2d0f5470-4b9e-4882-8f90-3d585e0c85b5/project_management_tools_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ef871412-600a-49a8-a84c-3d6f10b3245f/jokufujuxafi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c76c6751-a9be-43c1-b33e-632555a7de9f/renenov.pdfIn PDF document text
    • http://butorinowu.myartsonline.com/sociology_of_education_in_canada_karen_robson.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e1e27987-9d40-4872-bea8-172ae6f83662/ford_explorer_sport_trac_2002_specs.pdfIn PDF document text
    • http://pavosalilob.rf.gd/2016226869.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3a08fa38-b757-4ffd-b592-31fb71988404/62939756078.pdfIn PDF document text
    • http://movafomuwexowix.epizy.com/parizuxewasiwomisiw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1c4f6f4a-0e1b-4ab1-860e-16dbb87a3744/hard_lateral_thinking_questions.pdfIn 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_off000115eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115EB 5236 bytes
SHA-256: 4eabc345a1e5f6f2ec86170fd515f15b40d71dadd1c4b7d13b0e57dc3d7bcda4
font_01_sfnt_off000127b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127B5 11044 bytes
SHA-256: 802af12a42fe2c03abc3347eff53026e9661e7ac6cf0ff8c060050e41f05fbe1