Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3c3718aa7d95ecc…

MALICIOUS

PDF

76.2 KB Created: 2021-03-16 21:54:14 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 0e1d3aa8de5138e59ac811cc02847452 SHA-1: 2166404880d8e944e636f12e82e9c015a8b923d5 SHA-256: b3c3718aa7d95eccbb885cfb1d950a04848726b7a1f204bb630d0c580022f71e
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many hosted on disposable domains, which is characteristic of a link farm used for phishing or distributing further malware. The ClamAV detection and ML classifier strongly indicate malicious intent. The embedded URLs are the primary indicators of compromise, likely leading to malicious content.

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
  • 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.
  • 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://nipisod.ru/strik?utm_term=staples+shredder+lockout+key+manual PDF link annotation
    • https://kizubunutasi.weebly.com/uploads/1/3/5/3/135348794/9465036.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4496824/normal_5fdbe55f6537a.pdfIn PDF document text
    • https://xizevidunofi.weebly.com/uploads/1/3/4/3/134321119/kefajobedetagol-jekuvigebol-vugizubikab-vomudexunagif.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413369/normal_60092acf3bc46.pdfIn PDF document text
    • https://cdn.sqhk.co/gubogezemazo/jj8Oiap/kafinejodulinesenivugek.pdfIn PDF document text
    • https://xakowuval.weebly.com/uploads/1/3/5/3/135316831/nexumux_fipumupe_luxideju.pdfIn PDF document text
    • https://cdn.sqhk.co/zejizoguzut/jiznFih/lixoxakofukusedareru.pdfIn PDF document text
    • https://cdn.sqhk.co/bezizafosu/Ajjgfie/best_chess_tactics_puzzles_app.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410975/normal_601d0b0ec6e58.pdfIn PDF document text
    • https://cdn.sqhk.co/fefavezevir/AyjfeMU/marketing_guideline.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486199/normal_6017fbe10fd6c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385631/normal_602f1ceaa8d98.pdfIn PDF document text
    • https://cdn.sqhk.co/fasotaluvose/hmdF2tS/alien_zone_plus_mod_apk_an1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://d03ec42c-8b93-48d3-a61e-9aee396c0db4.filesusr.com/ugd/1e557c_35a7c6ea3f994ae7b284e88bd846d02a.pdf?index=trueIn PDF document text
    • https://09972071-4174-499b-90b1-de3619f59f53.filesusr.com/ugd/d1c05f_ed99ed4e58b64d7491ffb860347b06fb.pdf?index=trueIn PDF document text
    • https://bad3f395-1638-4667-b349-d6f934eeab49.filesusr.com/ugd/ed2d23_1701765417ad4501a17aaedd4cbd63bf.pdf?index=trueIn PDF document text
    • https://11ab4cf5-156d-4417-99e9-5039b2a7eb5f.filesusr.com/ugd/82d61e_00c878268631470e95866defd4fce1f8.pdf?index=trueIn PDF document text
    • https://667abc8f-92ca-45d9-bc9d-789c80a68858.filesusr.com/ugd/dcd78f_a5879a9c88a74ef98446b802edae4435.pdf?index=trueIn PDF document text
    • https://48bf584d-d56c-45cf-b4f3-c1c05dce5274.filesusr.com/ugd/3f4b99_e42ff10aa5ee46bb9bf35c2f6148bc3f.pdf?index=trueIn PDF document text
    • https://0b670cc3-d94b-4117-8b98-7ce677fb6c21.filesusr.com/ugd/7bc559_2d65eb492c924048b6c401571d8ed682.pdf?index=trueIn PDF document text
    • https://434dcbc4-7bd9-40fe-99bf-e102daebf961.filesusr.com/ugd/07ef24_3187b675bfe242fa9688ea11f91b6daa.pdf?index=trueIn PDF document text
    • https://ab60d57a-1f92-408f-9079-0b325776b613.filesusr.com/ugd/724fb5_baedf32b73214ed5884702715f84a2f4.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_off0000e8a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8A8 5580 bytes
SHA-256: 223b1db825b8e2b818e173eb6499d993b20dfa579372d97938bfb4697e4fff10
font_01_sfnt_off0000fb7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB7E 11784 bytes
SHA-256: f80f998fcf1777756966b6067dd8e411dfbb6790a5bfae0700b94ad6829cfae4