Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b3cafb2488d13c8…

MALICIOUS

PDF

74.7 KB Created: 2021-03-29 01:26:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 8b4df872d239df20223f05a6f2ccddd2 SHA-1: 56bbecbc9f1f842f667646e6ff67d9dff3fe3757 SHA-256: 2b3cafb2488d13c85d2108b61b4d543fa8c99bf69f94a9860ca1b6e6900772df
126 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains numerous external URIs, with a primary focus on `https://xajibur.ru/strik?utm_term=statistical+physics+lecture+notes+pdf`, suggesting it's part of a link farm designed to redirect users to potentially harmful content. The document's structure and embedded links point towards a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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 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://xajibur.ru/strik?utm_term=statistical+physics+lecture+notes+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4412606/normal_6046fcbd2ac84.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4483083/normal_5fce0b427647c.pdfIn PDF document text
    • https://cdn.sqhk.co/duwenaxiseve/fkn91aI/14259829617.pdfIn PDF document text
    • http://penaxuwilamufo.iblogger.org/ranupuvaj.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409417/normal_5fe7707ee5cc2.pdfIn PDF document text
    • https://cdn.sqhk.co/kubabulukod/DgjfbJn/miromarizigidukeb.pdfIn PDF document text
    • https://cdn.sqhk.co/xovepejegosi/upjXYie/xagalagosaxakafawa.pdfIn PDF document text
    • https://cdn.sqhk.co/rapowipijes/bhaqjgK/jungle_boy_strain_names.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367944/normal_6052809354aa7.pdfIn PDF document text
    • https://cdn.sqhk.co/tobamozusaj/jchj4XG/23417375887.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452398/normal_60432de489e18.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4482880/normal_5fedce715b605.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415739/normal_602fbcf1753bc.pdfIn PDF document text
    • http://rirenanevigi.22web.org/gedubenuguzuw.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/c656d817-4c0d-4254-9a78-9d42cc1d4bdd/check_codes_on_2012_jeep_wrangler.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7303f9d1-4aa0-4ac2-bac1-bfb660ef2b67/apft_push_up_sit_up_standards.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/50cf97c6-f1e0-4e75-945c-581ef9903801/dna_transcription_and_translation_worksheet_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9dd29237-bbde-4fbb-82bb-4259afd68c66/4220422670.pdfIn PDF document text
    • http://ritanuwo.epizy.com/nezodidapetekanaxe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e1b660b2-afc1-4b1f-a187-e4b49702ba0d/what_is_constant_failure_rate.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5cd5a4c6-757e-40bc-a2a3-8181442be90a/what_verse_says_all_things_are_possible_with_god.pdfIn PDF document text
    • http://kutoduno.rf.gd/aston_villa_v_west_ham_match_report.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6cebd28b-c9fa-4837-91b9-967744d9760a/dirt_devil_power_max_xl_bagless_upright_vacuum_cleaner_reviews.pdfIn PDF document text
    • http://nederanunotaz.rf.gd/essential_spanish_grammar.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4033a210-a092-48df-9593-c543b2adf4a0/how_much_does_a_data_scientist_make_uk.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_off0000e458.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE458 5448 bytes
SHA-256: ef0e2ba5567fcf64d8f37d7a90af7f795d8605e6e801adf779417a8aa36c1ead
font_01_sfnt_off0000f6de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6DE 11320 bytes
SHA-256: a949ba5d2e4a15092b5a8696c4a6fbc79692c5a37f504a1fd1af338354c82060