Malicious PDF — malware analysis report

Static analysis result for SHA-256 bcf585cfc9fff9f6…

MALICIOUS

PDF

81.5 KB Created: 2021-05-15 04:48:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: ae50047f34acf5538a7f752d02f282d8 SHA-1: a0f4af528a875d126851564a0bbcd2f8ebf9c22e SHA-256: bcf585cfc9fff9f6c5d2b36968c875e0e9da64ce283a9b92847db29d388fb3dc
126 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded external links, many of which point to disposable hosting services, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the structure and numerous external links suggest a phishing or redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 5

  • 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://pelibifir.ru/strik?utm_term=what+age+is+watership+down+for PDF link annotation
    • http://raxejudesezix.scienceontheweb.net/fotatilu.pdfIn PDF document text
    • https://bemujegifa.weebly.com/uploads/1/3/5/3/135312506/9465092.pdfIn PDF document text
    • https://rubosesizip.weebly.com/uploads/1/3/4/7/134744628/2577123.pdfIn PDF document text
    • http://letxxnx.org/cuales_son_las_mejores_ciudades_para_trabajar_en_estados_unidosmwmga.pdfIn PDF document text
    • http://bukobaxaz.getenjoyment.net/difepozebadewukogenaxet.pdfIn PDF document text
    • http://katermore.ru/65020556369k1ng1.pdfIn PDF document text
    • http://gekiwejal.scienceontheweb.net/practically_speaking_download.pdfIn PDF document text
    • http://melowimaz.getenjoyment.net/anxiety_disorder_types.pdfIn PDF document text
    • https://ralirepiputup.weebly.com/uploads/1/3/4/8/134852471/2438600.pdfIn PDF document text
    • http://pumba-timon.space/honey_bee_songst5fjp.pdfIn PDF document text
    • http://torixewiser.medianewsonline.com/wujanapufujonilizamab.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://626fb5af-1d67-41cb-86ce-204163677ff0.filesusr.com/ugd/9d869b_366c9bb925464c5ca84488c685a8e414.pdf?index=trueIn PDF document text
    • http://punotonaduwize.atwebpages.com/87593115919.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8a487174-e2b1-4f36-b4e4-dc3607d8cdf3/97264612668.pdfIn PDF document text
    • https://c809e8a6-5bdf-489d-8d8c-df4e4638a115.filesusr.com/ugd/45a296_a9e80c23215d419da5897ba7d1678d4c.pdf?index=trueIn PDF document text
    • https://6c473ef0-402e-45f0-9f95-6bc7e89a6a1a.filesusr.com/ugd/5518c3_d9ae986cbc5941ac85df57369c11584e.pdf?index=trueIn PDF document text
    • https://3f3b26af-a357-4ab7-b723-baa2d0f6bb2b.filesusr.com/ugd/5d6e2e_c115c69f5d87416dbbb5c037b3250c44.pdf?index=trueIn PDF document text
    • https://83bd47e3-138d-48d8-8d00-514fe13b91b0.filesusr.com/ugd/c87a2f_744759e9c4484db8bd410f911b65e546.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/41e47bdc-db1c-429a-8637-ec2cfb60ee96/poulan_pro_weed_eater_fuel_line_diagram.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ee08114b-a944-482a-a57e-6b9944bf99c5/how_to_stop_cat_anxiety.pdfIn PDF document text
    • http://bepolujogox.atwebpages.com/bomemubasudutijotezev.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/91c03b08-43ef-4875-b2bf-a97ea8a9b1a3/65225902718.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f8e5d53e-7a9e-4dd4-97c3-3a6300bd5898/combining_like_terms_algebra_worksheet.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_off0000fed4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFED4 5376 bytes
SHA-256: 2044e31ba2ea7ab770fed6b9c30457d64d3bffb6d16f08887371976f5766d09e
font_01_sfnt_off00011137.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11137 11320 bytes
SHA-256: 823a47a33468b3c4ab8f2a0da5e4fef4f9908e713ba72972e9c62ecb9e95a268