Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c532ec921c8b283…

MALICIOUS

PDF

79.4 KB Created: 2021-06-10 03:26:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 4b4456a078ee13bd94b106fcb2cc8e64 SHA-1: 9ea7b17ffa47ae112575e9216eb17fdb7b36bb15 SHA-256: 4c532ec921c8b28366ed6c1f9a4106b7b9c140ff484f495daf423a64449e79aa
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 0.9996

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/123?utm_term=bcdedit.+exe++windows+8 PDF link annotation
    • https://gogukosujupubof.weebly.com/uploads/1/3/5/3/135317205/tabalusarufiniz.pdfIn PDF document text
    • https://toxilitabosi.weebly.com/uploads/1/3/4/4/134495834/wuvotaki_jofulukamup_jefog.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375195/normal_5fd8cac2567ff.pdfIn PDF document text
    • https://mizevazorabij.weebly.com/uploads/1/3/5/3/135347525/mamisedosevo.pdfIn PDF document text
    • https://tanibegaw.weebly.com/uploads/1/3/4/6/134600132/gezapazupefase-watit-matexorufaz-pereweju.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4500665/normal_5fcf352061230.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4412161/normal_5fcf338b0e76e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448718/normal_60bd1d8ecb86f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4409393/normal_5fcd3bd7792aa.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/bc877bc1-582b-41f0-b390-34f358c306a3/75777506659.pdfIn PDF document text
    • http://fotikeralo.pbworks.com/f/sinp_job_approval_letter_sample.pdfIn PDF document text
    • http://sisagexal.pbworks.com/f/gesodivimutoresesitixuf.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/99ef3349-7837-4026-8f8a-8bfc27583ab5/how_to_determine_scale_length_of_bass.pdfIn PDF document text
    • http://gazoridixilu.pbworks.com/w/file/fetch/144529686/rotusadozavojulajeze.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/49d6a51d-69cb-46e9-95e3-6271dc94bd14/is_the_fallout_series_overseers_office.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dbbf7865-525e-46f6-83cc-ca2fdffa902b/jewapokawadolugujotesumob.pdfIn PDF document text
    • http://xofitesu.pbworks.com/f/sofuli.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7b10aa55-80d0-4176-a779-01c250fcdc86/marketing_plan_excel_template_2019.pdfIn PDF document text
    • http://kedetuwi.pbworks.com/f/4120922494.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1d9b2e01-749d-4cd9-b452-8fbf40839304/how_to_get_free_robux_2020_codes_june.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/627934a2-8ef0-45ce-81bf-07f6f788356b/fosilarelenunuxetova.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6fdafe48-af39-45bb-995a-ff7a3718506d/gojomax.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_off0000f677.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF677 5028 bytes
SHA-256: a3c0ccb16f342b03b80514c29617d6e8c18bc8abfb89a87598f92d9820bb9469
font_01_sfnt_off000107c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C9 11772 bytes
SHA-256: 667d03d6507e4bcd13fc80813d0549e1741de7987ffdc40b7520b6e0ffc6d451