Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5a5903737617fab…

MALICIOUS

PDF

80.6 KB Created: 2021-04-17 10:03:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 798a1c3e8c9ae3269691640dfe43852f SHA-1: d9638ad06b7393376653f73b5bc2a27e5d96768a SHA-256: a5a5903737617fab730cd87da6780d00f638e59800e46ea95339398289e04cae
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to disposable domains and are likely part of a link farm. The document body, though heavily obfuscated, appears to be a lure related to a movie title. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or redirection to malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • 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.
  • 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/strik?utm_term=el+nombre+de+la+rosa+pelicula+completa+gratis
    • http://kernig.online/jirisujatupanuwopunugu2a5r.pdf
    • http://girlita.space/harmony_dreamtime_deluxe_comfort_booster_car_seat_reviews4uner.pdf
    • https://static.s123-cdn-static.com/uploads/4486367/normal_5ffb2e0cf01d9.pdf
    • http://you-bestshop.xyz/565652228843hde5.pdf
    • https://cdn.sqhk.co/sosobita/iahjkij/wedding_cake_toppers_personalized_motorcycle.pdf
    • https://cdn.sqhk.co/wanadujogo/gwozCUn/among_us_online_unblocked.pdf
    • https://cdn.sqhk.co/tuwagezo/RBBoPv6/editing_text_online_free.pdf
    • https://cdn-cms.f-static.net/uploads/4501774/normal_604de747aa4a1.pdf
    • http://worelimupuvefam.mywebcommunity.org/golds_gym_stride_trainer_350i_elliptical_instruction_manual.pdf
    • http://invitesistem.ru/wuduledajupigevhap3f.pdf
    • https://cdn.sqhk.co/metevetufi/icjc0Qz/consignment_stores_open_near_me.pdf
    • http://gufutaca1.xyz/81749755766o3vm9.pdf
    • https://cdn-cms.f-static.net/uploads/4427093/normal_601dad6dd17d5.pdf
    • https://cdn.sqhk.co/daborofus/gJabhgK/13351792410.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://7f1d4f38-7308-4051-b389-b8ed31312188.filesusr.com/ugd/e948c1_4b07a2c590cb41489477b75aa416a4eb.pdf?index=true
    • http://gofumakexoj.onlinewebshop.net/present_perfect_tense_vs_present_perfect_continuous_tense_exercises.pdf
    • https://42f4b946-f871-4f2a-a73e-6571c6569919.filesusr.com/ugd/e20521_e5b090565a884e44ac303caad7491f3c.pdf?index=true
    • https://e25b5f36-ee09-4010-8803-019b2853a23b.filesusr.com/ugd/c34eac_0ff636f0f2934bf2a95bdae858c20cd8.pdf?index=true
    • https://00e6f838-d17c-4130-b616-1adf5f4d9bb3.filesusr.com/ugd/714321_88c2b803640f4053ac55841f00931f84.pdf?index=true
    • https://7920a853-f458-4dfc-a893-f50c3ed6f780.filesusr.com/ugd/fe7850_a4a1fb82fb394295a41e1b196a3e5566.pdf?index=true
    • https://df256b98-640c-444d-885a-8195c7360722.filesusr.com/ugd/40b9e6_964c2b0332514069b2f793670de8a975.pdf?index=true
    • https://ecad98c5-3f79-4b5a-9309-7060426a101e.filesusr.com/ugd/66ec94_52318fd164764713b20289b60bbac8cc.pdf?index=true
    • https://33b7cf8b-1cb2-46d9-9063-17e97cba5e80.filesusr.com/ugd/9edd50_a4a05379d4254d359295ee61dab97199.pdf?index=true
    • https://5c71d6b4-13b5-43a2-97a4-9a0eba4d0f4d.filesusr.com/ugd/0f1814_80c739ebe6c54c879b214382c17ccaab.pdf?index=true
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec8b.bin
f81086e4bd3bbd8c79a6cf57f0eca60444b3ae8d63caafd9f5dd67bd61132d8f
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC8B 5372 bytes
font_01_sfnt_off0000fea4.bin
2d60c5474a86cead16cdb022c2b2c66196e59fc70cafb5e0930719692854583b
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEA4 12164 bytes
font_02_sfnt_off0001266e.bin
4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3
pdf-font-stream PDF embedded font (sfnt) at offset 0x1266E 4324 bytes