Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6702c58b88b4ed3…

MALICIOUS

PDF

77.7 KB Created: 2021-03-25 04:05:44 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: cffa80ed3f3a53690aaa50f231f84d0e SHA-1: c51052564b221a6f2c41257890399e2f1df67415 SHA-256: a6702c58b88b4ed3accc53009f9d93b6e157877c5dcf437638355f4334909cb7
66 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable domains and are likely part of a link farm designed to redirect users to malicious content. The ML classifier strongly indicated maliciousness, and the PDF structure suggests it's designed to exploit user curiosity by presenting seemingly legitimate educational material that links to potentially harmful sites. No scripts were extracted, but the high number of suspicious URLs and the ML detection point to a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 4

  • 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://leonvi.ru/123?utm_term=3d+shapes+worksheets+6th+grade PDF link annotation
    • http://sarawavenudiwap.mygamesonline.org/algae_biotechnology_products_and_processes.pdfIn PDF document text
    • http://dusikazo.mypressonline.com/alzheimer_fisiopatologia_2020.pdfIn PDF document text
    • http://design-kvartira.info/kenwood_kdc-mp245_wiring_diagram7fx7o.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477173/normal_60571a6d3214a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4461509/normal_5fd26a4d0b4c5.pdfIn PDF document text
    • http://mesutilixuta.sportsontheweb.net/presidents_during_the_republic_of_texas_tended_to_coalesce_around.pdfIn PDF document text
    • http://zuzorovix.scienceontheweb.net/apush_amsco_book_2015.pdfIn PDF document text
    • http://vsedlyatebya.xyz/xuan_feng_shao_nu_2x20vd.pdfIn PDF document text
    • http://lezigovedavide.getenjoyment.net/windows_10_bash_python_command_not_found.pdfIn PDF document text
    • http://laulu-go.ru/68547035671br1tn.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414851/normal_605b6f8847906.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456420/normal_602b46ff609a1.pdfIn PDF document text
    • http://beautysss.site/1168282307bxwfv.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4421366/normal_6002b3abd791f.pdfIn PDF document text
    • http://tiktokfrance.fun/sat_reading_sample_test8ke7e.pdfIn PDF document text
    • http://kixurox.getenjoyment.net/tajuwivas.pdfIn PDF document text
    • http://lenuvivureropi.scienceontheweb.net/par_quoi_peut_on_remplacer_la_feve_tonka.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8d5bcf17-53f2-4f21-b585-7a27aef14131.filesusr.com/ugd/7baf93_72c9d41c823e4f16961796d32bffccba.pdf?index=trueIn PDF document text
    • https://78ff948a-0765-49f5-a22c-0fbe0eba7848.filesusr.com/ugd/888d0b_dad67d9bc1e0459d923c870e53972c9a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/38ec6321-7990-43a8-828f-785dbd2b652f/free_english_conversation_lesson_plans_for_adults.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b128726b-09d9-4452-8d06-85c0a8e9eaa9/vopakevunetoved.pdfIn PDF document text
    • http://nozozuwovore.atwebpages.com/synonyms_and_antonyms_worksheets_grade_7.pdfIn PDF document text
    • https://8b83d164-5e56-46cc-b941-48f48810ddf3.filesusr.com/ugd/76ce43_b85dc4d0b37d4994896210385a65fc90.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6ca3bbe9-a63c-42f9-ae29-a7dee8babb02/dimikazumizip.pdfIn PDF document text
    • https://4993f9ff-345c-4c03-a8ec-d4f8dac664d6.filesusr.com/ugd/debbe1_9cb763d81144432e8ae12261bf2aa442.pdf?index=trueIn PDF document text
    • http://widifusi.myartsonline.com/31169290520.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/66925cef-6f36-484f-a05c-96ce3e11d86d/tasco_trail_camera_replacement_parts.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_off0000f27b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF27B 5568 bytes
SHA-256: db861e5495e7f6c7bfa96fa8a2b96105a14526790ce3cc05295defdbce7b78e1
font_01_sfnt_off0001057b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1057B 10436 bytes
SHA-256: 18fd5926ec36ab5c9bda9421beb4da026da837b8fca0c83994f78538188062cf