Malicious PDF — malware analysis report

Static analysis result for SHA-256 21a74684a6e7b4ab…

MALICIOUS

PDF

86.2 KB Created: 2021-04-29 18:42:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: b0de50387614ac2350a3bf37791cb85c SHA-1: 16db23ea1c3bae406f59a4bcbaeba23736ff38b7 SHA-256: 21a74684a6e7b4ab1bfee006c4c6fbeabd371a9a199a9dc3aa5be263f5ff3c42
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO spam operation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing or malware sites. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a malicious document designed to exploit users through external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://botokaw.ru/strik?utm_term=what+to+say+when+someone+asks+you+to+be+godmother PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4498801/normal_6040777cc42ba.pdfIn PDF document text
    • https://woxawilafuzuve.weebly.com/uploads/1/3/4/6/134669094/lamoza_zopesapibew.pdfIn PDF document text
    • http://werenntaq.online/cloud_engineer_salary_in_london2c3ds.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427097/normal_6063353a92338.pdfIn PDF document text
    • http://lnstagram-help-businesss.com/covalent_compounds_naming_worksheeteuix2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379221/normal_603a7c1c69f8a.pdfIn PDF document text
    • http://zarabotok.space/social_studies_chapter_9_study_guidej1f8x.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4460230/normal_6007b558ebef9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388626/normal_602166ec897df.pdfIn PDF document text
    • http://setofexperience.site/lijajobuyxv.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376369/normal_6056f150434ef.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4420745/normal_5fefc70c46a2a.pdfIn PDF document text
    • https://totijavefukaja.weebly.com/uploads/1/3/4/7/134705726/d0f33.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383444/normal_602ba50100498.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464878/normal_60254753d39dd.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/nakuzafol/strategic_management_concepts_and_cases_competitiveness_and_globalization_13th_edition.pdfIn PDF document text
    • http://getidevip.epizy.com/halloween_history_national_geographic_worksheet.pdfIn PDF document text
    • https://s3.amazonaws.com/penefelomiju/37763523828.pdfIn PDF document text
    • http://xugamux.epizy.com/antonym_word_search_puzzle.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000efdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFDF 5616 bytes
SHA-256: ec7bc3b79aeb754cadbca63ec96a5c9b602cb00a82de1178fc93502136899e95
font_01_sfnt_off000102de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102DE 1648 bytes
SHA-256: db10b07aa1ba911afaf060b12e2cde8c70dbbf9941f30369d108722010ce9547
font_02_sfnt_off00010b28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B28 12004 bytes
SHA-256: 67bd510a96ffca10f5e03e10a21cee70013321d98dc4df9ce4fb3917b5f15914
font_03_sfnt_off000133fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133FB 16596 bytes
SHA-256: e59f6dd94cd032d12a733ed90bf1ad1e457e9488e2fe4698ad00a975386e6061