Malicious PDF — malware analysis report

Static analysis result for SHA-256 354cf65f564dc7c9…

MALICIOUS

PDF

75.1 KB Created: 2021-05-24 00:57:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 811117b89153b6d4ef53a651812ddec8 SHA-1: 8d5cb1e021c5b1d7bd605fbaf1cf2dae012de66f SHA-256: 354cf65f564dc7c98469a5d9b7925eb0cc9423a08ab3687659e78f34cb3269da
186 Risk Score

Malware Insights

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

The PDF contains a link farm with 30 external links, many pointing to disposable hosting, and one specific URL that appears to be a lure for malware or phishing. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to malicious content.

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://jacksth.ru/strik?utm_term=sample+appeal+letter+for+primary+school+admission PDF link annotation
    • https://tapidokebijimub.weebly.com/uploads/1/3/4/5/134577153/a8d088c9bb25f.pdfIn PDF document text
    • https://tinutenuku.weebly.com/uploads/1/3/4/6/134664278/setimafogovegom.pdfIn PDF document text
    • https://wiwoxedanin.weebly.com/uploads/1/3/4/0/134012493/supirefek_sixuguwexu_nagemosoju_wavoximefesotel.pdfIn PDF document text
    • https://ketoleva.weebly.com/uploads/1/3/4/6/134642234/dovexixozabiri.pdfIn PDF document text
    • https://timifuxi.weebly.com/uploads/1/3/4/6/134676324/307627c3bfb32a.pdfIn PDF document text
    • https://zoxiniguve.weebly.com/uploads/1/3/4/5/134584112/e344eed15d9.pdfIn PDF document text
    • https://fumabufoduf.weebly.com/uploads/1/3/5/3/135313851/kukek.pdfIn PDF document text
    • https://xufolonul.weebly.com/uploads/1/3/2/6/132695880/7197791.pdfIn PDF document text
    • https://pixamowogiru.weebly.com/uploads/1/3/4/5/134590731/bifotubarojulul.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/fifomi/in_what_order_should_i_watch_the_girl_with_the_dragon_tattoo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2c48d980-2fb0-4bf8-9493-2036d38b86a1/tidututosinoretelo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/68b214f8-d78e-4772-a2f5-54bc35b39e6e/amplificadores_de_sonido_para_casa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/816b07e7-2168-45dc-90f0-90e8261f355e/the_vampire_diaries_season_8_episode_16_trailer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0cea6b5c-c141-43f4-9369-2761505f94ff/luzisobadijevewutuf.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d3b46412-e861-402b-b223-76ddf57f4ec1/21088533756.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c47a0ab1-a8a8-4bd6-a129-603170663a29/costos_de_calidad_ejemplos_de_empresas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fdc4765b-3fdc-4422-a609-3f1d5296728f/vatabunabisekigibubadi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ccecada1-724f-417d-8c13-ffe3ac43f80a/51892627694.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2c0b39e0-f08a-47d9-8a51-ebec4a94b640/rebadavoxiwelapuju.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7545ce27-882a-4df9-b807-783aac8ddee4/rusokuxobusabo.pdfIn PDF document text
    • https://s3.amazonaws.com/ropidadegaxut/55862599453.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7db9a772-69cf-4868-931a-994b22af71bf/95311470405.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_off0000e793.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE793 5600 bytes
SHA-256: 93502a2b359b73648e3a5386478807ad9a02e0c24f89d0143fa064f0cb3b82ee
font_01_sfnt_off0000fa78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA78 10520 bytes
SHA-256: 351c62f4505f8951207f29e2dbbe5809b9578921645c69960780485e28deb056