Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd855e38c0fefeff…

MALICIOUS

PDF

81.8 KB Created: 2021-03-14 01:09:32 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 3c2c4ec38206b2a263e624faefc63818 SHA-1: bd90bbbcb8f73fdf30deea835421ed2ba25447ce SHA-256: bd855e38c0fefeff0219215282b541660fd2e98e34f5b27408d953578812a23d
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://fokemale.ru/123?utm_term=sarcastic+answers+to+are+you+awake PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4378607/normal_60157dc571732.pdfIn PDF document text
    • https://zitolibozix.weebly.com/uploads/1/3/4/0/134040523/235e715d8b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481520/normal_604d45e38d1ac.pdfIn PDF document text
    • https://pobufulali.weebly.com/uploads/1/3/4/4/134494274/6646154.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4381543/normal_5fff6cc77dbc0.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://932aa67c-856a-4fda-9fc8-fe3f50d4acc2.filesusr.com/ugd/a25eee_dcd9ab25aa474de5a8f892768d977cfb.pdf?index=trueIn PDF document text
    • https://ddf64d59-5240-4154-9987-17dfc28e22c7.filesusr.com/ugd/cec570_a4aca78e11ee4199826803bbb43566e6.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/591f24aa-6b93-4368-9e55-731adba5e6c6/fresh_off_the_boat_restaurant_orange_beach.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6442e3c0-e76c-42f2-93fe-feec4d95498a/65587049634.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8f748815-f1a4-4037-9fe6-6e460c5e2041/daily_bible_reading_plan_in_chronological_order.pdfIn PDF document text
    • https://2863666b-9d79-467d-9aad-9eeb6dafbdf2.filesusr.com/ugd/6ee3eb_65568af8ec7d4062b413c971ba3ff4f1.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/2491cd3d-d583-484b-b0e1-36f43066d5fb/19095677163.pdfIn PDF document text
    • https://bf68d742-fb98-404a-ab47-1dcf24f7df52.filesusr.com/ugd/83e7fd_7fa638409aa04e8099e130a9e49e4c93.pdf?index=trueIn PDF document text
    • https://de99c131-68bf-4271-bcef-cda292486844.filesusr.com/ugd/f5892c_77be29ccf5774d5fa5bd1da2d58d8452.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/38aa21ba-3648-4b4d-81f3-c743d378e10d/warhammer_fantasy_battle_starter_sets.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/507fe4c3-16b7-4fe0-99f1-1b244f0bac17/the_secret_book_in_hindi_summary.pdfIn PDF document text
    • https://72a23b54-95c1-47c0-80d6-f7b1310faeb8.filesusr.com/ugd/65b209_726b4e6b42c742ebb6c0368d2839f719.pdf?index=trueIn PDF document text
    • https://7be326e9-a1fd-4761-a84c-83c904220737.filesusr.com/ugd/37e945_d38e895641ed41dca0976a232052de2b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/36bdf5b1-e596-4770-bbdb-6842fd607ce1/dulakonid.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/83b9758e-5ad5-446d-ab36-820fbca6255d/sony_dream_machine_auto_time_set_model_icf_c218_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/db75cf6f-69e3-4a2e-a7d8-7796b618dc59/how_to_do_pen_and_ink_drawings.pdfIn PDF document text
    • https://d5cf7a15-73c9-49c9-ad57-d4f0303abb0c.filesusr.com/ugd/0d002d_2099e475d91d4c1cb68c64b71830c776.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/56d66df1-2729-4d34-b36b-1f97e188a83a/samsung_rf4287hars_water_filter_part_number.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_off0001030a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1030A 5120 bytes
SHA-256: 7f78f0d14afa47e8ac8ea04182963610c870d4944f07156dcbcfb4c04e63f0af
font_01_sfnt_off0001149f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1149F 10760 bytes
SHA-256: 35bf9a64ec69958718ff8f86b07de1f56895d5152dd6ed64b89884a9c64690d0