Malicious PDF — malware analysis report

Static analysis result for SHA-256 3811e9b38cab2570…

MALICIOUS

PDF

78.0 KB Created: 2021-05-08 08:55:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: d152503a286343041159a8be54f0f2a5 SHA-1: 21b8284b0d233387b466436801ea5ab347875eec SHA-256: 3811e9b38cab25706de61736dcc20664ff27c651a832ffc0d184867ebe0b3298
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 as a link farm, with many pointing to disposable hosting. ClamAV detected this as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The primary function appears to be redirecting users to potentially malicious websites, consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://druttle.ru/strik?utm_term=clasificacion+de+numeros+decimales+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4470223/normal_6036f61d04a4a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405641/normal_60286f164cc9d.pdfIn PDF document text
    • https://cdn.sqhk.co/netimawifes/hfhcnVt/tunobemanitofubigesiton.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4498366/normal_6049955aa4f8a.pdfIn PDF document text
    • https://ranibifuvif.weebly.com/uploads/1/3/1/3/131381542/motigatipese.pdfIn PDF document text
    • https://minadefimufev.weebly.com/uploads/1/3/4/6/134635785/4874703.pdfIn PDF document text
    • https://cdn.sqhk.co/lagusive/bYP61gh/xotogojam.pdfIn PDF document text
    • http://milatepe.medianewsonline.com/84402300775.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4414502/normal_5fc8e36bc820f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4387040/normal_5ffa3a206ea7f.pdfIn PDF document text
    • https://cdn.sqhk.co/kigudukolon/ndjbjib/mixusula.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471960/normal_6015d74497907.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409258/normal_606490c0bce2a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388060/normal_606c881b59cb1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388824/normal_6063f347c2790.pdfIn PDF document text
    • https://sebiwijojemobod.weebly.com/uploads/1/3/4/0/134097571/2513dff8.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4448357/normal_5fdd6f6aa8630.pdfIn PDF document text
    • https://cdn.sqhk.co/dudofolejune/jNLzidp/vuvorumizitavurafogiverud.pdfIn PDF document text
    • https://cdn.sqhk.co/sileluzorupo/sOjaXN6/rightmark_audio_analyzer_6._2._3_free_download.pdfIn PDF document text
    • http://luxisulejoxo.getenjoyment.net/dudinutokevid.pdfIn PDF document text
    • http://xisumagogali.getenjoyment.net/how_to_find_a_child_in_foster_care_arizona.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fotizojorirepel.onlinewebshop.net/pdf_negritude_movement.pdfIn PDF document text
    • https://s3.amazonaws.com/nuvukivaxiren/75983666658.pdfIn PDF document text
    • https://s3.amazonaws.com/fedufiporara/john_deere_trs21_carburetor.pdfIn PDF document text
    • https://s3.amazonaws.com/turip/zadivalovonabufinu.pdfIn PDF document text
    • https://s3.amazonaws.com/setikizo/camp_x_ray_dual_audio_720p.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_off0000eecf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEECF 5208 bytes
SHA-256: 0f4c02912a40bd1141ed2bf101f9b49229989e670c2f55ea3086234bb6ae33eb
font_01_sfnt_off00010068.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10068 12240 bytes
SHA-256: aa84a4599162f20414b7ca73b3d8367209f02a032e78ff19b5f96508251f2b06