{"schema_version":"0.10.0","id":"LR-2026-0542","record_version":1,"title":"Google Chrome silently downloads 4GB on-device AI model without permission","verification":{"human_verified":false,"method":"automated_gate","auto_verified":true,"score":46.0,"score_breakdown":{"source_authority":12.1,"independent_corroboration":7.0,"implicated_party_confirmed":0.0,"citation_integrity":14.0,"specificity":3.0,"completeness":2.56,"unhedged_language":5.0},"checks":{"schema_valid":true,"every_field_cited":true,"quotes_verbatim":true,"source_fetched":true,"distinct_incident":true,"dates_plausible":true,"sources_agree":true,"source_describes_incident":true,"severe_backed_by_source":true,"record_integrity":true,"eligible":true,"about_this_case":true},"gate_version":"gate-2026-10-18.7","cross_check_model":null,"cross_check_agreement":null,"duplicate_of":null,"verified_by":null,"verified_at":"2026-11-01","extraction_run_id":null,"evidence_level":{"level":"preliminary","reason":"1 report: Tom's Hardware · subject to change","original_document":null,"reports_total":1,"reports_independent":1,"reports_derivative":0,"developing":false,"disputed":false,"rules_version":"evidence-2026-10-29.1","computed_at":"2026-11-01","history":[{"date":"2026-11-01","from_level":null,"to_level":"preliminary","reason":"1 report: Tom's Hardware · subject to change"}]},"sources_hash":"2de0d038ccfa62993835289879fd8091fd8d82a5809668a162012dbcb936ba76"},"system":{"model_name":null,"model_version":null,"developer":"Google","harness":null,"tools_granted":[],"permissions_scope":null,"autonomy_level":"unknown","guardrails_present":[],"deployment_context":"unknown","tier":null,"lifecycle_stage":null,"integration_type":null,"intended_use":null,"safeguard_state":null,"production_intended":null},"event":{"date_occurred":null,"date_disclosed":"2026-05-06","incident_class":"other","failure_class":null,"agent_involved":null,"secondary_failure_classes":[],"trigger":"unknown","duration":null,"detection_method":"public_researcher","summary":"Google Chrome, according to security researcher Alexander Hanff, downloads a roughly 4GB on-device AI model file named weights.bin, part of its Gemini Nano feature, to users' machines without notice or consent. Hanff says there is no clear consent flow, no prompt explaining the download, and no straightforward setting to prevent it, and that the file is re-downloaded if deleted. In a controlled test on a fresh Chrome profile on macOS, using operating system filesystem logs, he reports the browser created the model directory and downloaded the full payload in the background during idle browsing with no human interaction. Chrome's internal state files reportedly show the machine was marked eligible for the model before the download. Hanff's claims have not been tested in court. Google had not publicly responded in detail at the time of writing.","tags":[],"date_detected":null,"near_miss":null,"root_cause":null,"root_cause_detail":null,"failure_class_detail":null,"responsible_party":null,"adversarial_actor":null,"input_provenance":null,"time_to_contain":null,"operations_paused":null,"remediation":null,"precursor_events":null},"impact":{"direct_loss_usd":null,"remediation_hours":null,"records_exposed":null,"third_parties_affected_count":null,"severity":"moderate","harm_class":[],"affected_description":"users' machines that meet certain hardware requirements","protected_class_involved":null,"data_categories_exposed":[],"loss_range_usd":null,"reversibility":null,"downstream_exposure_count":null},"evidence":{"sources":[{"url":"https://www.tomshardware.com/tech-industry/cyber-security/google-chrome-silently-downloads-4gb-ai-model-to-your-device-without-permission-report-claims-researcher-says-practice-may-violate-eu-law-waste-thousands-of-kilowatts-of-energy","publisher":"Tom's Hardware","date":"2026-05-06","type":"press","title":"Google Chrome 'silently' downloads 4GB AI model to your device without permission, report claims — researcher says practice may violate EU law, waste thousands of kilowatts of energy - Tom's Hardware","archived_url":null,"attachment":"first_report","independence":"independent"}],"per_field_confidence":{"system.developer":"C","event.detection_method":"C","impact.affected_description":"C","event.incident_class":"D","impact.severity":"D","event.summary":"C","system.autonomy_level":"D","system.deployment_context":"D","event.trigger":"D","context.country":"D","event.date_disclosed":"D","context.denominator_available":"D"},"field_citations":{"system.developer":[{"source_index":0,"quote":"Security researcher Alexander Hanff, also known as \"That Privacy Guy,\" has published a new analysis claiming that Google Chrome is silently downloading a roughly 4GB on-device AI model to users' machines without notice or consent."}],"event.detection_method":[{"source_index":0,"quote":"Security researcher Alexander Hanff, also known as \"That Privacy Guy,\" has published a new analysis claiming that Google Chrome is silently downloading a roughly 4GB on-device AI model to users' machines without notice or consent."}],"impact.affected_description":[{"source_index":0,"quote":"The file is approximately 4GB in size and is downloaded automatically on systems that meet certain hardware requirements."}],"event.incident_class":[{"source_index":0,"quote":"Security researcher Alexander Hanff, also known as \"That Privacy Guy,\" has published a new analysis claiming that Google Chrome is silently downloading a roughly 4GB on-device AI model to users' machines without notice or consent."}],"impact.severity":[{"source_index":0,"quote":"The file is approximately 4GB in size and is downloaded automatically on systems that meet certain hardware requirements."}],"event.summary":[{"source_index":0,"quote":"Security researcher Alexander Hanff, also known as \"That Privacy Guy,\" has published a new analysis claiming that Google Chrome is silently downloading a roughly 4GB on-device AI model to users' machines without notice or consent."},{"source_index":0,"quote":"In his latest post, he says Chrome is now writing a file called \"weights.bin\" to disk, part of the company's on-device AI system based on its lightweight Gemini Nano model."},{"source_index":0,"quote":"According to Hanff, there is no clear consent flow for this download."},{"source_index":0,"quote":"Users who discover and delete the file will find it re-downloaded later unless they disable certain experimental flags or remove Chrome entirely."},{"source_index":0,"quote":"To verify what was happening, Hanff conducted a controlled test using a fresh Chrome profile on macOS."},{"source_index":0,"quote":"According to his analysis, the browser created the model directory and downloaded the full 4GB payload in the background while no human interaction was taking place."},{"source_index":0,"quote":"These show that the browser evaluated the system's hardware capabilities and marked it as eligible for the on-device model before the download occurred."},{"source_index":0,"quote":"These claims have not been tested in court, but they reflect a growing tension between aggressive feature rollout and regulatory expectations, particularly in Europe."},{"source_index":0,"quote":"Google has not publicly responded in detail to Hanff's findings at the time of writing, and the company may argue that these downloads are tied to legitimate product features and improve privacy by keeping AI processing local."}]},"notes_on_gaps":"Single press source (Tom's Hardware) relaying a researcher's analysis; Google had not responded in detail, so Chrome's behaviour is unconfirmed by the company. No occurrence date is stated; the 2026-05-06 date is the article date used as disclosure date. The download duration is only stated as 'just over fourteen minutes', so no exact duration was recorded. The source does not describe an autonomous agent, so agent fields, failure class and trigger were left out. Root cause, responsible party and remediation are not stated and were left out. Severity 'moderate' is my judgement from the bounded-scope sentence about hardware requirements; the environmental table figures are the researcher's hypothetical estimates and were not used as impact values. The B1 'missing' link is my mapping of the absent consent step to the human-approval control, which is an analogy rather than a stated control. Developer 'Google' is inferred from the article's reference to the company's Gemini Nano system in Chrome. The EU-law claims are unresolved and not tested in court, so no legal harm class was recorded. [case created by the backfill: read by claude-haiku-5-5, backfill-2026-11-01.2, 2026-11-01; not yet reviewed] [2026-11-01: evidence level set: Preliminary (1 report: Tom's Hardware · subject to change)]"},"context":{"industry":null,"org_size_band":null,"country":"unknown","denominator_available":false,"denominator":null,"related_incident_ids":[],"systemic_exposure":null,"shared_model_id":null,"upstream_incident_id":null,"incident_evidence":null,"regulatory":null,"coverage":null},"narrative":{"steps":[{"step":"went_wrong","text":"According to the researcher, there is no clear consent flow for the download.","quote":"According to Hanff, there is no clear consent flow for this download.","source_index":0,"grade":"C"}],"model":"claude-haiku-5-5","prompt_version":"backfill-2026-11-01.2","extracted_at":"2026-11-01","source_urls":["https://www.tomshardware.com/tech-industry/cyber-security/google-chrome-silently-downloads-4gb-ai-model-to-your-device-without-permission-report-claims-researcher-says-practice-may-violate-eu-law-waste-thousands-of-kilowatts-of-energy"]},"analysis":{"sections":{"timeline":[{"text":"During the test, the browser creates the model directory and downloads the full 4GB payload in the background.","quote":"According to his analysis, the browser created the model directory and downloaded the full 4GB payload in the background while no human interaction was taking place.","source_index":0,"when":null},{"text":"The download process completes, in just over fourteen minutes, during apparent idle browsing time.","quote":"The process completed in just over fourteen minutes, during what appeared to be idle browsing time.","source_index":0,"when":null}]},"model":"claude-haiku-5-5","prompt_version":"backfill-2026-11-01.2","extracted_at":"2026-11-01","source_urls":["https://www.tomshardware.com/tech-industry/cyber-security/google-chrome-silently-downloads-4gb-ai-model-to-your-device-without-permission-report-claims-researcher-says-practice-may-violate-eu-law-waste-thousands-of-kilowatts-of-energy"]}}