Malicious PDF — malware analysis report

Static analysis result for SHA-256 536762be7cbe0df5…

MALICIOUS

PDF

81.7 KB Created: 2021-04-15 01:55:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 90022603f8b8e7b14cf92cf13b88be4d SHA-1: 4fd85ec8b0211af2f3ed97ade864c0e0e26cecd7 SHA-256: 536762be7cbe0df5aabb6dfa461d26e8ec1ad8ce46b4f4e1f128aad039a33442
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or redirection scheme. The primary URL, 'https://jacksth.ru/strik?utm_term=how+to+fix+jammed+bb+gun', suggests a lure to a malicious site. ClamAV detection and ML classification confirm the malicious nature of the file, likely as a phishing or malware distribution tool.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://jacksth.ru/strik?utm_term=how+to+fix+jammed+bb+gun PDF link annotation
    • https://cdn.sqhk.co/zezegawutogu/fLI6Nja/war_chess_3d_for_android.pdfIn PDF document text
    • http://dariduv.22web.org/adt_is_owned_by.pdfIn PDF document text
    • https://feronodi.weebly.com/uploads/1/3/0/8/130813799/zumigiraporim.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377912/normal_601e579f44033.pdfIn PDF document text
    • https://xotototovizeta.weebly.com/uploads/1/3/2/3/132303406/fifarubomotuk.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451225/normal_6002177cbbfb7.pdfIn PDF document text
    • https://wudigunufite.weebly.com/uploads/1/3/4/6/134611509/mozizetapuvaberad.pdfIn PDF document text
    • https://cdn.sqhk.co/tisewesir/s0vuwhg/city_racing_lite_game_download_for_pc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370073/normal_602e4f949a46c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422135/normal_6054e6c0d87b1.pdfIn PDF document text
    • http://sosixowadisi.iblogger.org/doctor_zhivago_2002_movie_download_free.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420432/normal_606e12b4b7557.pdfIn PDF document text
    • https://cdn.sqhk.co/jimavidozeze/dicjSyX/reaction_trainer_app.pdfIn PDF document text
    • https://zogowejodumuf.weebly.com/uploads/1/3/0/7/130775171/sileg_ledotejif_meraxo_kegumekisiviw.pdfIn PDF document text
    • https://cdn.sqhk.co/pugipepa/chdSZie/vitoxevufinatex.pdfIn PDF document text
    • http://midixub.iblogger.org/craftsman_wet_dry_vac_filter_model_113.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://3bcdeb60-9876-4d14-bc0a-1dd1632c647c.filesusr.com/ugd/16a96a_a81b6b882b1c4f6789a88484057d4aa0.pdf?index=trueIn PDF document text
    • http://jajapelemazibog.rf.gd/antigona_livro_completo.pdfIn PDF document text
    • https://db22a0a0-c6c8-4eb9-9878-037c50d93224.filesusr.com/ugd/e2b5b3_5d63babda6964bb08061e79f1032c9b7.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/d148ccf1-d675-48a9-8e22-5054afe2c3a6/3025460958.pdfIn PDF document text
    • https://1801fa0f-56e4-4894-8452-b8e06651d4be.filesusr.com/ugd/868401_ee36bf798917410a9539d473461f6999.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/666e82b3-1214-400a-9cda-7e3fa9523581/32789701418.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5fecd447-1ff6-4b7c-b244-4924d7b1c10e/what_deep_meaning_does_fire_and_ice_carry_in_it.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dd0f1e8f-2b51-474c-87b0-e42e15597224/90722490589.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_off0000ff23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF23 5256 bytes
SHA-256: f520737cb4fe72154c35252ef6e20c839143e158ca159bc3725228b247f528bc
font_01_sfnt_off00011113.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11113 11932 bytes
SHA-256: 41919412f5cebd8b677a564c9c4b36b34dc621bc020e48fb8f20373f31fa82e9