Malicious PDF — malware analysis report

Static analysis result for SHA-256 9516d989b45cbf66…

MALICIOUS

PDF

83.0 KB Created: 2021-04-06 15:34:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 276697675c9911853b7eb8365018b14b SHA-1: ced576414ca912a79cd8d6b5ffab1e18b31fbfef SHA-256: 9516d989b45cbf66ddf3b7ebe75442f84647c3890588c0c05ccf673f711723b0
186 Risk Score

Malware Insights

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

This PDF document is identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous external URIs, with one notable example being https://vilenefex.ru/strik?utm_term=what+are+the+best+romance+books. The document's structure and the presence of embedded links suggest an attempt to lure users to potentially malicious websites, likely for phishing or malware distribution. No scripts were extracted, but the PDF's nature as a link farm is a strong indicator of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • 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://vilenefex.ru/strik?utm_term=what+are+the+best+romance+books PDF link annotation
    • http://bowemesuzot.iblogger.org/samupopewujurirabemivi.pdfIn PDF document text
    • http://jamedoxeka.22web.org/pdf_to_word_converter_i_love_you.pdfIn PDF document text
    • http://kfnwejfnkwheklf.space/desesakumavii.pdfIn PDF document text
    • http://sfr-webmail.com/78652010562f01so.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://ebd73b9a-b255-48a5-b781-2bd84b483b4c.filesusr.com/ugd/956c05_8cbd61ba631f4d4e9d9d244b8f12bb5a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/bc37ffc4-fd69-4ea3-b6c6-bd3d026feaa9/is_he_testing_me_by_ignoring_me.pdfIn PDF document text
    • http://fotopokidag.epizy.com/the_scarlet_gospels_summary.pdfIn PDF document text
    • http://rizusuzapil.rf.gd/dihybrid_crosses_practice_problems_worksheet_answer_key.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ace827a1-d733-46fd-a6fb-db6460b6e7c2/fuwimofokusuluw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/674782a9-8119-43f3-9741-b306d3351138/limejinizosiruzuganurow.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/59afdedf-b466-42b8-9085-1904b162fd44/how_to_reset_hp_printer_2545.pdfIn PDF document text
    • http://gateguka.epizy.com/cancer_treatment_in_ayurveda.pdfIn PDF document text
    • https://73f4d879-981c-49fe-abc7-520f36a14a84.filesusr.com/ugd/b77b08_385d6b52d452470a822a18fe2a037ed6.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/cc630870-feca-44f1-937a-0a4f4e0be754/kreepy_krauly_kruiser_not_working.pdfIn PDF document text
    • http://vagenudutuxa.rf.gd/nunidoxevunib.pdfIn PDF document text
    • http://jalonuvupitu.rf.gd/el_ser_biopsicosocial.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a35e7826-e5fc-442e-8745-31f211bcc002/how_to_get_to_the_desert_in_links_awakening.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1b6ad4a4-8690-4df7-908d-19570360bb93/where_are_the_filters_on_my_dyson_animal.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_off00010610.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10610 5224 bytes
SHA-256: 128c5cea0e57b55d6129af16b20a3800301cc7d9808eff2e51e6d97b289f4e28
font_01_sfnt_off000117b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117B9 11644 bytes
SHA-256: 20202174d73da31f844dd5a28c8cdf3815bad860bd804460f376d66556731926