Malicious PDF — malware analysis report

Static analysis result for SHA-256 6424b83f10c00bf5…

MALICIOUS

PDF

83.2 KB Created: 2021-04-05 03:27:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: e152c8f319fd5b8f34a7ec90fc31bf06 SHA-1: 10a83995f26072c1689aaac790aec41b297d0620 SHA-256: 6424b83f10c00bf5edfab62573c184831f5154c8ffc2767d0fd95675a2a78751
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://gimoguvi.ru/strik?utm_term=how+to+reduce+multiple+photo+file+size+on+mac PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4478422/normal_5fc5706642dfa.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4386829/normal_5ff484de5b1aa.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4457560/normal_5fcf9fb4eab66.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4471253/normal_6007a1b165507.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/c6904c0c-6ced-44d3-b01f-01126e1e993b/wusiwojena.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8003ae98-920e-4b73-88ef-586e0fb5685a/3209099958.pdfIn PDF document text
    • https://s3.amazonaws.com/jajuzasalikirut/honda_generator_eu2000i_service_kit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8a3a4a9b-1914-4277-98fa-baaf1abe39f6/85714135957.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/49e61886-bce5-499b-9441-e2310dcd20d0/37765687070.pdfIn PDF document text
    • https://s3.amazonaws.com/tugumeb/32757966836.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/29f615d3-645d-441a-b9c4-087a5e1f94fd/how_much_do_air_force_jags_make.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bd107d04-ce4d-4ac7-a1a1-3b1d70e24d27/tegofoxudumera.pdfIn PDF document text
    • https://786c536d-253b-4a15-94df-129c4693a223.filesusr.com/ugd/1fc311_eaaeb3c3312147009a562ba89a46cde7.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/20069c32-63fa-42bb-90d6-44c03f14d87d/how_to_breathe_after_exercise.pdfIn PDF document text
    • https://d4cba69e-f3c5-4a64-9e40-69ba24924691.filesusr.com/ugd/b73feb_c8d764251cb24461a4412af268e23b51.pdf?index=trueIn PDF document text
    • https://5ec50ee2-6c76-415b-b731-82d7de26534b.filesusr.com/ugd/826e74_e39f30ad938f42ef9f40be3eb9a2273c.pdf?index=trueIn PDF document text
    • https://8319d365-0190-44ee-b2f3-e76f6fd230eb.filesusr.com/ugd/112488_88bad776283140808cc063be7781c3de.pdf?index=trueIn PDF document text
    • https://1a441fb4-51dd-4528-a053-eb59ff664e18.filesusr.com/ugd/43d9d5_f5ac9dd6cb8440fc8f2bb2b13b9c1c31.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/676fef06-4c15-49a2-b107-c1637b2d340f/what_electron_group_geometry_is_associated_with_sp_hybridization.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/11234d9e-c5cf-4430-8e55-41eac72a2fd5/how_to_remove_a_washing_machine_agitator_kenmore.pdfIn PDF document text
    • https://59e5a08b-0d8d-455f-a3a7-35a3b781ab3e.filesusr.com/ugd/784815_153642b70d0541538b946f9dbcbf9fcf.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/gumagabu/lexulolomukimex.pdfIn PDF document text
    • https://1c684d3d-b1aa-4d58-8f8e-408f9cf37fac.filesusr.com/ugd/64d889_25567642c8a44229ac98b3333514b9a0.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_off000106a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106A5 5500 bytes
SHA-256: 1bb781528bc4ee4f1123ceda723b1da0bfdc6cb15bc5c4cb365d7086b3feeca0
font_01_sfnt_off00011947.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11947 11000 bytes
SHA-256: 8f20c1144235fd7cb614b95571f242eac281fde8d6486d508589141356764f8a