Malicious PDF — malware analysis report

Static analysis result for SHA-256 b77a3f87120f52bc…

MALICIOUS

PDF

79.4 KB Created: 2021-04-01 12:03:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f46d0b418db457b6744afedabd224242 SHA-1: 86735c79c335aac992107f5f30a98fe4a7e97b56 SHA-256: b77a3f87120f52bcb82572981315734d1979ad0ed81ef53e9aa8f743123fc7ca
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable or suspicious domains, indicating a link farm or redirection mechanism. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and a date, suggesting it was generated programmatically to appear as a legitimate document, masking its true purpose of directing users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://maypoin.ru/award?keyword=beginner+s+guide+to+reading+schematics+fourth+edition+pdf
    • http://kisoxowizupoz.iblogger.org/maintenance_page_template_bootstrap.pdf
    • http://wozonos.22web.org/97034661802.pdf
    • http://vepekideku.iblogger.org/matlab_for_loop_character_array.pdf
    • http://dusosax.66ghz.com/habanera_sheet_music_voice.pdf
    • https://cdn-cms.f-static.net/uploads/4412767/normal_600a4f168cbe1.pdf
    • https://cdn-cms.f-static.net/uploads/4379380/normal_6058865353353.pdf
    • https://cdn-cms.f-static.net/uploads/4422373/normal_604e63d208eb1.pdf
    • http://wunuvuzixuxi.getenjoyment.net/reading_comprehension_3rd_grade.pdf
    • http://prizinsta24.site/9087019458tnzw7.pdf
    • http://gixipures.sportsontheweb.net/32176594221.pdf
    • http://afracheat1.xyz/visual_dictionary_of_architecture_2nd_editionm8v21.pdf
    • http://tradestaroffice.com/2004_dodge_ram_1500_5.7_hemi_lug_patternr8iqk.pdf
    • http://tells.fun/fejiwimixojij0w5m5.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/774be78b-f077-4686-83bd-a7f594ee85b7/91391576116.pdf
    • http://sifuzetijo.rf.gd/bilimokupiwabezetudu.pdf
    • http://bodiluduf.rf.gd/hound_of_baskerville_full_movie_in_telugu_hd.pdf
    • https://uploads.strikinglycdn.com/files/c87ae134-8696-4c4a-a221-7c3ef5c6efc2/20910754848.pdf
    • https://uploads.strikinglycdn.com/files/3489c7b3-b498-4675-b8a3-67eaf6c8dc2f/hobart_handler_140_mig_gun.pdf
    • http://koxikid.epizy.com/bach_air_on_g_string_sheet_music.pdf
    • https://uploads.strikinglycdn.com/files/b8fb4455-5d92-48f2-b6d3-4f5671a6277a/21159423350.pdf
    • http://mizetum.onlinewebshop.net/car_engine_diagram.pdf
    • https://uploads.strikinglycdn.com/files/1fa6a24c-1f0b-4e59-ab91-eb639ab3bcfa/terumegefose.pdf
    • http://waminakukivexo.rf.gd/mibuzasomume.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f79c.bin
73aa84fe9f963a79006f6eccf3410410a4cc546b759a0ba27c21731237a3a495		 pdf-font-stream PDF embedded font (sfnt) at offset 0xF79C 5588 bytes
font_01_sfnt_off00010a7a.bin
90af8f924ffc1b4e27a61f42bd5e03d091506fda4e5ec0ead4d7e6b18afbd5be		 pdf-font-stream PDF embedded font (sfnt) at offset 0x10A7A 11160 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.