Malicious PDF — malware analysis report

Static analysis result for SHA-256 787d82f3fd209c22…

MALICIOUS

PDF

71.6 KB Created: 2021-06-03 13:57:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 59e64934183d440662f45d320deae4fa SHA-1: c40d8e4eb46ba3dc25a8184bbdae04a57347ba25 SHA-256: 787d82f3fd209c220d3f5169b9cb3ac807aeb1d02def1b9554e314c0fc0b27d3
126 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains an embedded URL that redirects to a link farm, likely intended to host or redirect to malicious content. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and 'Qt', suggesting it was generated by a tool rather than being a legitimate document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://laborke.ru/pbw?utm_term=kindergarten+math+worksheets+addition+with+pictures PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4369164/normal_60110f66ab367.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4467955/normal_5fd7c6353103d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365659/normal_5fd6f490dc371.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4503524/normal_60329e5adec0d.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/b7c74d43-9212-4268-8587-0ee14032963b/sentry_safe_wont_unlock_with_code.pdfIn PDF document text
    • http://wuranosa.pbworks.com/f/mivugejipapudodoxuvo.pdfIn PDF document text
    • http://paderukut.pbworks.com/w/file/fetch/144468498/eng1503_assignment_1_answers_2020_semester_2.pdfIn PDF document text
    • http://pefagisunel.pbworks.com/f/twilight_breaking_dawn_part_3_full_movie_2013_in_tamil.pdfIn PDF document text
    • http://wiliser.pbworks.com/w/file/fetch/144556338/epoxy_fiberglass_insulation_sheet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/36200f82-2d56-42e9-b49b-53b9fbde04f7/best_ice_axe_for_mountaineering.pdfIn PDF document text
    • http://podimil.pbworks.com/f/derecho_penal_griselda_amuchategui_oxford.pdfIn PDF document text
    • http://dekokos.pbworks.com/f/33807703083.pdfIn PDF document text
    • http://pevozowo.pbworks.com/f/nogopobidutibodukufokul.pdfIn PDF document text
    • http://funinupun.pbworks.com/w/file/fetch/144427140/10_oraciones_separado_sujeto_predicado_y_verbo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ba1e6bc-5e4b-4906-820d-40916e901e78/kalesasezuzodedotozomurab.pdfIn PDF document text
    • http://lipadune.pbworks.com/w/file/fetch/144427176/catcher_in_the_rye_important_quotes_with_page_numbers.pdfIn PDF document text
    • http://jobojifitin.pbworks.com/f/63781475980.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c02989e5-6117-4684-b79f-8af312b8c9f4/what_is_the_main_effect_of_climate_change_in_mekong_delta_vietnam.pdfIn PDF document text
    • http://nidibewuzi.pbworks.com/f/how_to_install_frigidaire_ice_maker_for_top_mount_refrigerator.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2b2f0d1b-d91a-4d8e-8f86-dbe5355d0080/descargar_cambridge_advanced_learners_dictionary_3rd_edition_gratis.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3958ed65-5f0e-450d-997f-b751cee9aae6/formula_para_hallar_el_punto_de_equilibrio_en_pesos.pdfIn PDF document text
    • http://damopijos.pbworks.com/w/file/fetch/144499710/93932619459.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9e37ab44-7a0d-4f6d-b73b-d9eabdb41f4c/what_is_the_price_of_samsung_tab_a6.pdfIn PDF document text
    • http://kokoxudalux.pbworks.com/f/399103363.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_off0000db5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB5D 5580 bytes
SHA-256: 74e4550481d20ca6f5c89eacda154866debba48256d44ac9624e3f95cb043435
font_01_sfnt_off0000ee3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE3D 10092 bytes
SHA-256: 9cb632d00ddbd4fb69220d7d26ec5b8a8a96f4f00328a44234617df7de212416