Malicious PDF — malware analysis report

Static analysis result for SHA-256 ee8750ef32ad25b0…

MALICIOUS

PDF

83.5 KB Created: 2021-05-18 18:43:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 9afff8b34c669e20218f16d34d17b793 SHA-1: c94b21eab221f1754ab15feb104586e7df5b382a SHA-256: ee8750ef32ad25b0f99153d03d4dbf744d9a1979890b57cdb2ab5799a504dba8
126 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, indicating a link farm or SEO spam operation. One of the primary URLs extracted is `https://ponafet.ru/strik?utm_term=how+to+pair+sub+to+lg+sound+bar`, which is likely part of this scheme. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent behind the link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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://ponafet.ru/strik?utm_term=how+to+pair+sub+to+lg+sound+bar PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4378852/normal_6037b3ea0ce9a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453103/normal_603b7b9a3e3eb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422908/normal_6050c595d6828.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387713/normal_602a1c5263b7f.pdfIn PDF document text
    • https://bopidojosonek.weebly.com/uploads/1/3/1/3/131384153/5786806.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446784/normal_601f604b1934e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370267/normal_6056ac6fe166d.pdfIn PDF document text
    • https://nizosanaradeke.weebly.com/uploads/1/3/4/8/134856136/nufukegozajom.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464542/normal_603ee6e0ab0d9.pdfIn PDF document text
    • https://luzidasagozoro.weebly.com/uploads/1/3/4/3/134319964/b0fab9acc5.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/352342d8-e4e1-4726-a9fe-9f916280a9ee/moon_phase_worksheet_answers.pdfIn PDF document text
    • http://dipexukojudiz.rf.gd/81601018672.pdfIn PDF document text
    • https://s3.amazonaws.com/nokiva/thailand_on_arrival_visa_form_for_indian.pdfIn PDF document text
    • https://s3.amazonaws.com/bevekizadoxuj/kizonulisokemajepa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0512c158-e346-4fe4-acd5-6968bd854d7d/subject_verb_agreement_worksheets_grade_1.pdfIn PDF document text
    • http://vegiroromofi.rf.gd/cabinet_secretariat_recruitment_2020.pdfIn PDF document text
    • https://s3.amazonaws.com/fizufapu/power_of_now_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a637d3e5-553b-49db-b5cd-84c3e3188b2d/cc3_selected_answers_chapter_8.pdfIn PDF document text
    • http://suredutika.rf.gd/vameta.pdfIn PDF document text
    • http://lodusuvixad.rf.gd/tirelutifefuvilanazowenep.pdfIn PDF document text
    • https://s3.amazonaws.com/sonutopexaramuf/barasesawa.pdfIn PDF document text
    • https://s3.amazonaws.com/jefazaxal/where_does_the_term_manners_maketh_man_come_from.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/53fbe65d-ecfc-4c5c-86d0-9fd87f2c55f6/ruxame.pdfIn PDF document text
    • http://mujozigimak.rf.gd/29574118566.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_off000106a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106A8 5320 bytes
SHA-256: fe877e058891453fb4c15ba55a36bd86b1815b226de04acbe7a833b7bda2a2da
font_01_sfnt_off000118d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118D2 11040 bytes
SHA-256: 90b4f17baa69b630cf3caed5858bae4a8294ef607febedb9167a9334c5439fec