Malicious PDF — malware analysis report

Static analysis result for SHA-256 b72729ea9c2012c7…

MALICIOUS

PDF

74.0 KB Created: 2021-03-07 15:44:30 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 98871a4ad850a2534c5ec81e546b4815 SHA-1: fa76ae14e7ad94d28dbff1419dff99af49c222e3 SHA-256: b72729ea9c2012c71aeff24fc2c2c28d4ab72591fc8ea7f6cbfc42d58707192a
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ClamAV and an ML classifier, and contains numerous embedded links. One critical heuristic indicates the PDF links to known malicious redirector infrastructure, and another identifies it as a link farm on disposable hosting. The document body is heavily obfuscated and unreadable, suggesting it is not intended for human consumption but rather to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/award?keyword=the+heart+of+yoga In PDF document text
    • https://cdn.sqhk.co/palezubifo/hjcG8if/gunebafuji.pdfIn PDF document text
    • https://cdn.sqhk.co/gisanewat/iDjgBif/warlings_armageddon_2_hack_apk.pdfIn PDF document text
    • https://cdn.sqhk.co/wuluzajiroz/eheRZii/the_dead_walk_among_us.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4469365/normal_5fd93c1501440.pdfIn PDF document text
    • https://cdn.sqhk.co/keridola/Fahd2gf/26436260584.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384464/normal_5fe1bd32ea30d.pdfIn PDF document text
    • https://cdn.sqhk.co/joremeve/didhdYw/auction_sniper_free_snipes.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487381/normal_6039388bc1187.pdfIn PDF document text
    • https://cdn.sqhk.co/kisasizaro/aihFhc4/cats_clash_epic_battle_arena_strategy_games.pdfIn PDF document text
    • https://cdn.sqhk.co/fegojujor/MjbO8o8/suligajuwixuvo.pdfIn PDF document text
    • https://cdn.sqhk.co/vimewiki/Qjdkxhd/atlanta_home_restoration_company.pdfIn PDF document text
    • https://cdn.sqhk.co/vujenibolo/NhbjaGv/70210664215.pdfIn PDF document text
    • https://cdn.sqhk.co/kifukuvitog/hdib8hh/ships_of_glory_online_warship_combat_kits.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://48e4e0df-78ce-4736-8797-27735e68dc67.filesusr.com/ugd/f3b179_7b972d87e37b4e738bfef37ce5585116.pdf?index=trueIn PDF document text
    • https://855e1e5b-0daf-4dce-aa73-dfad2bfec5df.filesusr.com/ugd/ced2dc_8dba0c1180b349d3a75a835fcd8d8a6f.pdf?index=trueIn PDF document text
    • https://f3b8d348-8566-49c9-a9f8-a2c3b9e1bc8e.filesusr.com/ugd/f1c748_081bd5277a604a3792c96f8f6bc460e6.pdf?index=trueIn PDF document text
    • https://1d812fcc-cfc3-4558-a870-56fc5b7f4c2e.filesusr.com/ugd/754d94_94a8666e93bc4f8cbbcce181bfea0857.pdf?index=trueIn PDF document text
    • https://2061f665-9309-41a6-981d-137229ee7e60.filesusr.com/ugd/eb2fe6_d9c52cd815a74aa1816d9f817d7c5d30.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/mubefula/lukatenemabax.pdfIn PDF document text
    • https://s3.amazonaws.com/votawawo/58554965695.pdfIn PDF document text
    • https://b3709dad-42f4-4621-9b7e-74d31ca978cd.filesusr.com/ugd/f91cf1_bee1bad4762549859936da44c25e99ec.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/numegubowalonan/osrs_99_smithing_guide_f2p.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_off0000e6d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6D9 4872 bytes
SHA-256: 0a76089519f312ff9be004fa6e33bd51dde4dfe45bdb39381321cb4c0fc5ce18
font_01_sfnt_off0000f772.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF772 10196 bytes
SHA-256: 7eca09697c4fd66190003363db2d96fbd689b02e90b59f40d969b290cf2d20f8