Malicious PDF — malware analysis report

Static analysis result for SHA-256 161c1767031a8663…

MALICIOUS

PDF

71.2 KB Created: 2021-03-15 03:30:40 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: a32045cd7f7f85b5bbbea8ea33ce2f1f SHA-1: bd60fc81cb6f723b19efa60288417341b4cdaefa SHA-256: 161c1767031a86630de522894af0eb6217c32a65b74624194b1445c9da1fd2d2
126 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm on disposable hosting. The embedded URLs, such as https://jacksth.ru/wix?keyword=nc+foundations+of+math+1+pacing+guide, are likely used to redirect users to malicious sites. The PDF structure and numerous external links suggest an attempt to distribute malware or conduct phishing by masquerading as a legitimate resource.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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 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/wix?keyword=nc+foundations+of+math+1+pacing+guide PDF link annotation
    • http://airet.space/wodureb1bmgx.pdfIn PDF document text
    • http://gufopitasuwo.22web.org/82464075379.pdfIn PDF document text
    • http://ccckkkkk.space/solo_exhibition_proposal_example65gos.pdfIn PDF document text
    • http://uspex22.online/tozonamiwobory7jkl.pdfIn PDF document text
    • http://supernefritroller.xyz/bofezorilavaluverol7mr.pdfIn PDF document text
    • http://liolika-rsya.ru/64242162523v90af.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4422622/normal_5fe2bc935ce39.pdfIn PDF document text
    • http://tk-pobeda.site/tofonohibwh.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380379/normal_60434c8cc7ae4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369928/normal_60274e62f056d.pdfIn PDF document text
    • http://mandarin-fruit.space/bazekopuwehge8h.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://sixipiboronid.rf.gd/2004_dodge_ram_1500_fuel_pump_check_valve.pdfIn PDF document text
    • http://volegurez.rf.gd/sex_education_season_2_ending_explained_hindi.pdfIn PDF document text
    • https://s3.amazonaws.com/xonaxevetaf/math_word_search_answers.pdfIn PDF document text
    • http://miwunomo.epizy.com/is_it_illegal_to_use_a_ham_radio_without_a_license.pdfIn PDF document text
    • http://sofugudoz.rf.gd/how_do_you_take_apart_a_keurig_to_clean_it.pdfIn PDF document text
    • http://ramasewo.epizy.com/cover_lagu_hanya_rindu_della_firdatia.pdfIn PDF document text
    • https://s3.amazonaws.com/jidosatikim/dopujikifolaxu.pdfIn PDF document text
    • http://kewivifonawati.epizy.com/25093158730.pdfIn PDF document text
    • https://s3.amazonaws.com/zizene/betomowefawovujifefurus.pdfIn PDF document text
    • https://s3.amazonaws.com/dojonuta/firefawikedafim.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_off0000d929.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD929 5464 bytes
SHA-256: 95c92e91ff81cbdeeb2143f33e6cda01fcc75f5a7df9d7e68c0c0abacb6662d1
font_01_sfnt_off0000ebb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBB0 10356 bytes
SHA-256: ab5f77e16169ea22b324e146d7db7aa88efd32994b5bd64cbd91eea547b64a66