Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e70c998def3b503…

MALICIOUS

PDF

77.4 KB Created: 2021-05-09 08:52:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 2a8b3656f975b51b96d022d979da1ff0 SHA-1: 491dbf91a9f7c32a3fa9817bec38519e7faa4a26 SHA-256: 3e70c998def3b5031aa02d258d37e1a8631adba829fdad0a8b4f04b7c9faef98
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 0.9997

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://midufefew.ru/strik?utm_term=manual+de+gram%25C3%25A1tica+pdf PDF link annotation
    • http://ruxenawuxovogu.getenjoyment.net/budget_forms.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444648/normal_60373d7b2cdc6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390324/normal_60639649143ae.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459055/normal_5fc5cbc57dedf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417980/normal_6016d7d49133c.pdfIn PDF document text
    • http://suvuxivenorum.mypressonline.com/6443940830.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://bff5fdab-9fd0-4670-908b-a1308bb5a9cb.filesusr.com/ugd/227d0f_567da0199129481d9ba81efe6f27411a.pdf?index=trueIn PDF document text
    • https://ab9101c8-a046-40a0-ba79-761bab9f3367.filesusr.com/ugd/61fb7c_9b471ded7f7b4ce3b4bfd5306009d03e.pdf?index=trueIn PDF document text
    • https://8eefcaf3-52f5-4123-8be5-b1f0aaeea45e.filesusr.com/ugd/1d3654_17c9d3565c2747f0b6beb7dcec7a106a.pdf?index=trueIn PDF document text
    • https://c6f55193-7475-4343-97dd-33cb3b141b6a.filesusr.com/ugd/808d8c_aa524547f02f44408407a246d2b13443.pdf?index=trueIn PDF document text
    • https://8767aa75-4bd5-48c0-94ca-24e983238001.filesusr.com/ugd/debdc1_f29723213faa4dcc99b5d7ceab92c719.pdf?index=trueIn PDF document text
    • https://b998fa74-583e-446a-a2a7-67f41460fdb2.filesusr.com/ugd/e081f8_53d735d0b8554fd4b5efcfa660ee78e8.pdf?index=trueIn PDF document text
    • https://6cdf8c5e-36a0-4b6d-987f-32d3d50030cd.filesusr.com/ugd/3c2e2e_a104f908024a4e8ea8fb96377324f36f.pdf?index=trueIn PDF document text
    • http://dezinolabebosod.atwebpages.com/litadulobonepodamironuti.pdfIn PDF document text
    • http://salajire.onlinewebshop.net/child_care_leave_application.pdfIn PDF document text
    • https://s3.amazonaws.com/jevopemosod/78258888706.pdfIn PDF document text
    • https://s3.amazonaws.com/numunenoji/adanga_maru_bgm_songs_masstamilan.pdfIn PDF document text
    • https://s3.amazonaws.com/mizeteb/cipherlab_8000_scanner_manual.pdfIn PDF document text
    • https://s3.amazonaws.com/zinudipir/5585596431.pdfIn PDF document text
    • http://nabulegewuwal.myartsonline.com/i_ready_grade_4_math_book_answers.pdfIn PDF document text
    • https://3568ea06-17fa-4787-91ae-86b9aa918cbd.filesusr.com/ugd/8ade13_8090c67291564e0d84a4a47a5fc59a8e.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_off0000ef20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF20 5536 bytes
SHA-256: ccef0bf6c3e07f24dabee77fd249307e55fbe7b547e420293e2535ffe54ac86d
font_01_sfnt_off00010167.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10167 10952 bytes
SHA-256: 56ded4de9b218acb9a1320847094a8b74babdcdb66471643b78f516e264fcabb