Malicious PDF — malware analysis report

Static analysis result for SHA-256 a608546cc343c2af…

MALICIOUS

PDF

72.1 KB Created: 2021-03-22 09:20:52 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 66db60dc96f6c7e6a9bf80946b7fb7ee SHA-1: 9fb9392eac874541ed6eefe8fa6f11c18b0578b5 SHA-256: a608546cc343c2af8f91474cd858729bde90e4dfd3288a358e3d60b0b1770878
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm used for phishing or malware distribution. The document body, though heavily obfuscated, appears to be a lure related to a 'Lewis dot diagram chem worksheet key'. No scripts were extracted, but the PDF structure itself facilitates the redirection to malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://golowaki.ru/strik?utm_term=lewis+dot+diagram+chem+worksheet+5-7+key PDF link annotation
    • https://cdn.sqhk.co/pujixefan/jijgieR/fibopaxurivaridisip.pdfIn PDF document text
    • https://cdn.sqhk.co/nogawevorus/cjehche/advertising_agency_jobs_atlanta.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443325/normal_6019846d06c14.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458616/normal_603d7c8170827.pdfIn PDF document text
    • https://cdn.sqhk.co/gesuxafom/Q4he7hg/mimpi_gigi_bawah_copot_semua_pertanda_apa.pdfIn PDF document text
    • https://cdn.sqhk.co/rozesivotix/hj9zLkY/tiny_bubbles_laundry_arlington_tx.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4445731/normal_5fcf6156dae44.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386074/normal_60107a844b1f6.pdfIn PDF document text
    • https://cdn.sqhk.co/jotepomi/GFmVif8/77207331265.pdfIn PDF document text
    • https://cdn.sqhk.co/busumodofu/mlHhcjb/jikoroletelewumuse.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366359/normal_602af6d2cc7ae.pdfIn PDF document text
    • https://cdn.sqhk.co/rukububibon/jhienzY/gun_shot_fire_war_apk_download.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425737/normal_5fe1efc0a4d21.pdfIn PDF document text
    • http://vujereki.22web.org/car_accident_report_sample.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366032/normal_5ffc92a03497b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481052/normal_6016a7d57ccbb.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416150/normal_5fc87212da458.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://82e7f058-9c2a-4352-8e65-a162d98cde11.filesusr.com/ugd/ba3c76_74638ab7f8694f189e269a3594d3954c.pdf?index=trueIn PDF document text
    • https://5366dd3f-28a3-4342-b8e5-5bed86455aec.filesusr.com/ugd/a92322_79e982c8db2f4a88981716cbe9ea6ce5.pdf?index=trueIn PDF document text
    • http://xafamikipu.epizy.com/alaris_capture_pro_limited_edition.pdfIn PDF document text
    • https://2fe0a9f4-4d23-48c4-8711-d5fb25093877.filesusr.com/ugd/683a75_03fb60d090ad4b23a6dd1814329e5cbf.pdf?index=trueIn PDF document text
    • https://12f7643e-9106-4823-89c2-0bdaecd1bc22.filesusr.com/ugd/1f6d71_cb4113760bfd4228b8ada2af95875c6e.pdf?index=trueIn PDF document text
    • https://11627308-8c8f-4f08-99ed-0ad85160907d.filesusr.com/ugd/682d1c_6ef57b05b52a4258b39dc588a5f228d8.pdf?index=trueIn 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_off0000db39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB39 5756 bytes
SHA-256: a19e43a799a0e85a3e132d8062ea626841f6c0e6682ccc712213b2f6d83618aa
font_01_sfnt_off0000eeda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEDA 10620 bytes
SHA-256: 2d8ce85ccff036ab976cf5d0523964d4482c6070af82abc5383399e4940d8b57