Malicious PDF — malware analysis report

Static analysis result for SHA-256 51741fa8650c3611…

MALICIOUS

PDF

71.8 KB Created: 2021-02-28 20:33:16 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 55ed33fa6f3a40cda67e9c47dfb8a287 SHA-1: 18bfd3c9179c98490df7bd3ef40a1e54c8aa8d8e SHA-256: 51741fa8650c361199c85528dd7552f250f85819d50b329461d41efa8eb1c94a
244 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm and routes users through malicious redirector infrastructure. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/strik?utm_term=pentair+intellichlor+ic20+troubleshooting In PDF document text
    • https://wiraxupafetob.weebly.com/uploads/1/3/2/6/132696263/6385747.pdfIn PDF document text
    • http://design-kvartira.info/48769133643o8ozw.pdfIn PDF document text
    • https://dijafujuzu.weebly.com/uploads/1/3/4/3/134369935/439787.pdfIn PDF document text
    • http://bowemesuzot.iblogger.org/d_d_character_sheet_app_5e.pdfIn PDF document text
    • https://lozibojugor.weebly.com/uploads/1/3/1/0/131069840/kaxepibos.pdfIn PDF document text
    • https://ropumalopiku.weebly.com/uploads/1/3/4/6/134613257/bd3996aae379.pdfIn PDF document text
    • https://nimifitirujaga.weebly.com/uploads/1/3/4/6/134693460/fesisesi_xedifejaneme_lafox_vijemupokipir.pdfIn PDF document text
    • https://kurinasuvofete.weebly.com/uploads/1/3/5/3/135334761/f2442193979380e.pdfIn PDF document text
    • https://mifopezuzata.weebly.com/uploads/1/3/4/4/134484464/gizena.pdfIn PDF document text
    • http://lovemecompletely.com/12959613881drlg9.pdfIn PDF document text
    • http://topepuxabi.iblogger.org/best_chess_books_for_beginners_free.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/sinamozagemoger/fusesozomigula.pdfIn PDF document text
    • http://kixasudasiwub.epizy.com/39606916316.pdfIn PDF document text
    • http://sanugifop.atwebpages.com/what_holidays_is_the_federal_reserve_closed.pdfIn PDF document text
    • https://s3.amazonaws.com/kizugokofo/16802216563.pdfIn PDF document text
    • https://s3.amazonaws.com/davolazupivowi/affective_domain_assessment_tools.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_off0000db40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB40 5476 bytes
SHA-256: e593aa4317d3221caf267751333ca7d01e718b567850d3fbc61d19b769b6e4ef
font_01_sfnt_off0000edd1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDD1 10772 bytes
SHA-256: 7774db23ca668d900daa5b3fbe8506a8ad434ea152a0e9988af23c110c916163