Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4185b677fb2809f…

MALICIOUS

PDF

70.0 KB Created: 2021-04-07 10:44:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 3cad0c2c21bd907f6f933517c8531ec1 SHA-1: 7f057140a8c64b30132d3135159f7439a27cb609 SHA-256: b4185b677fb2809f4b5ef2aaf1536d7926d51c7aa90e6823617fb6f334e38a99
126 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as a phishing trojan and by a machine learning model with high confidence. It contains numerous embedded URLs, many pointing to unknown or potentially malicious domains, suggesting a phishing or malware distribution attempt. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a deliberate effort to create a link farm on disposable hosting, further supporting the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://baarspo.ru/wix?keyword=principles+of+biology+2+lab+manual+answers PDF link annotation
    • http://pokypka.xyz/how_to_store_fermented_fruit_juiceehkeu.pdfIn PDF document text
    • http://blue-tick-central.com/67102757211yvo79.pdfIn PDF document text
    • https://cdn.sqhk.co/sojowidaz/ggiajcf/my_little_princess_wizard_secrets.pdfIn PDF document text
    • http://help-copyrightservice.xyz/55132354895ay5lt.pdfIn PDF document text
    • https://cdn.sqhk.co/gonolesuzam/eggsQiT/roxilarodimijixuweg.pdfIn PDF document text
    • http://fanilobepewe.sportsontheweb.net/sig_sauer_p226_enhanced_elite_40_for_sale.pdfIn PDF document text
    • https://cdn.sqhk.co/gapebeve/a7hiNsP/dark_dungeons_comic.pdfIn PDF document text
    • http://datab.vip/8998003435b0qdb.pdfIn PDF document text
    • http://gasurorir.sportsontheweb.net/adobe_reader_gratis_softonic.pdfIn PDF document text
    • http://ninuwekevap.scienceontheweb.net/cual_es_el_proceso_de_investigacion_cualitativa.pdfIn PDF document text
    • https://cdn.sqhk.co/bikugipozamu/FSphefn/download_demolition_derby_multiplayer_mod_apk_unlimited_money.pdfIn PDF document text
    • https://cdn.sqhk.co/nigalasiline/qyOLIih/good_schools_guide_australia.pdfIn PDF document text
    • http://topstudy.fun/note_20_ultra_review_cameral1146.pdfIn PDF document text
    • http://vkrowl.com/806689450zxlka.pdfIn PDF document text
    • http://good-production17.site/fifty_shades_of_grey_freed_soundtrack_download_android7l8qp.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/fosalizuzu/azure_machine_learning_tutorial.pdfIn PDF document text
    • https://s3.amazonaws.com/lakujusitejojet/15542991476.pdfIn PDF document text
    • http://pesetunal.onlinewebshop.net/english_articles_exercises_with_answers.pdfIn PDF document text
    • https://s3.amazonaws.com/tubukeganuji/5273980894.pdfIn PDF document text
    • https://s3.amazonaws.com/zuses/8835654359.pdfIn PDF document text
    • https://5c817321-7c0c-448b-959d-deb1da9fd788.filesusr.com/ugd/19103d_57383485b77d40d4863ed075bac3e9bf.pdf?index=trueIn PDF document text
    • https://f3c4034a-4a94-4c47-b6c5-0445626d7bf8.filesusr.com/ugd/655f09_31001b3c90d54f56ab190bd1120bac59.pdf?index=trueIn PDF document text
    • https://f18b8dc1-3ce9-44bd-8712-01435d039869.filesusr.com/ugd/b97cba_70e81af52e264696bd215083f200733e.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/redegelesibif/how_to_cook_for_dummies_free.pdfIn PDF document text
    • https://f421159b-d329-41e8-bc42-072bc93e4c50.filesusr.com/ugd/65d6f7_8e49c3523a644675a2122082ac931676.pdf?index=trueIn PDF document text
    • https://76bf09fe-c378-4d6f-baa9-beaf48595a8b.filesusr.com/ugd/61567a_4dc15065d6ff48b4aede63ddb5602344.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_off0000d27f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD27F 5800 bytes
SHA-256: 944ce18e3d54b387a1389d29bc9193c5ed4fe77e9ecbe547e0a69493d53d371d
font_01_sfnt_off0000e645.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE645 10620 bytes
SHA-256: 035c8382ef150e20e0dc816f2a2c2c7e8b3e60d89e27376a9b1899c0053bbeda