Malicious PDF — malware analysis report

Static analysis result for SHA-256 5518b61e83ba514e…

MALICIOUS

PDF

74.4 KB Created: 2021-03-23 10:36:10 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 544da51fd2d16d9829e502ab610e93bd SHA-1: b0b1cf959f28e170da8a678ec21b7c3a33b8da41 SHA-256: 5518b61e83ba514ef461db48912a9bd12a34c3080be845d5ef57304ac61cd836
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of external links, identified by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. The ML classifier and ClamAV detection strongly indicate maliciousness. The primary purpose appears to be directing users to a network of potentially malicious or SEO-manipulating websites, rather than delivering a direct exploit or payload within the PDF itself.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://botokaw.ru/strik?utm_term=is+there+a+need+for+real+estate+appraisers PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4470532/normal_6049ef162c40d.pdfIn PDF document text
    • https://cdn.sqhk.co/vemegunir/aa70fhd/36849768494.pdfIn PDF document text
    • http://regse.website/jojezuxolo2ea6l.pdfIn PDF document text
    • http://navaram.online/hackerrank_mcq_questions_with_answerst5biz.pdfIn PDF document text
    • https://cdn.sqhk.co/riketumes/gixgcje/60710306066.pdfIn PDF document text
    • https://cdn.sqhk.co/rajunakeb/FCVBiaw/burokebudiruviduvorenu.pdfIn PDF document text
    • http://weinmvc.net/41968594243m3pfu.pdfIn PDF document text
    • https://cdn.sqhk.co/budajawisore/ibFvggK/kuwavepurinepekunite.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476274/normal_60510e98e8609.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4484356/normal_6000a4bc91daf.pdfIn PDF document text
    • http://websporizlehd.com/what_are_the_three_types_of_heat_transfer_that_occur_in_earths_processesl49e6.pdfIn PDF document text
    • http://stepka2016.xyz/shakespeare_how_many_plays_sonnets_and_poemsyumc8.pdfIn PDF document text
    • https://cdn.sqhk.co/zipirevofu/gXicgfB/43869546710.pdfIn PDF document text
    • http://boxberry-24.cc/34926761438k3nxv.pdfIn PDF document text
    • https://cdn.sqhk.co/juzogimuju/91jdyib/10230550059.pdfIn PDF document text
    • http://andyhong.blog/508079640975vrry.pdfIn PDF document text
    • https://cdn.sqhk.co/tiwoxebu/1DjbSoQ/star_wars_galaxies_jedi_gameplay.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370268/normal_600d82f288ef1.pdfIn PDF document text
    • https://cdn.sqhk.co/wanadujogo/hbpjbhB/fire_boy_water_girl_2_unblocked_66.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8488b7ac-84bc-45ae-88ed-26841205fc59.filesusr.com/ugd/7cda3c_4800ee1b1b584e56a7f41f854e0054f4.pdf?index=trueIn PDF document text
    • https://91ca87c2-c493-4616-adaa-fbcec45394e1.filesusr.com/ugd/6116da_510095ad8f5c41fa8d6e8e4a4f0006c5.pdf?index=trueIn PDF document text
    • https://45ed8376-e832-497f-ab20-0a31924dc5db.filesusr.com/ugd/4b7290_bc1ce484f3934711b0078e041dfb7ac7.pdf?index=trueIn PDF document text
    • https://dd39d194-9042-494f-90ab-223c96cf8da5.filesusr.com/ugd/5d3909_1d43a6770ada40ad93d5b08d1d688400.pdf?index=trueIn PDF document text
    • https://36622f5a-5a1b-41a5-aa98-965156e47ac2.filesusr.com/ugd/804ff6_ce75abf709d5403a860db75c85e598c2.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_off0000e76d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE76D 5068 bytes
SHA-256: 8859e239996c905e091a970cd29fec059b09e96a5d49afe2c6cec0b0bec64505
font_01_sfnt_off0000f8a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A2 10448 bytes
SHA-256: 5723d96af462c15e4c25d12c63e681aa8b9742b3156e0d022ebb54304bf9639c