{
 "public_id": "AIR-2026-0009",
 "incident_id": "2026-01-trailofbits-agentic-browser-isolation",
 "date_disclosed": "2026-01-13",
 "date_occurred": null,
 "title": "Lack of isolation in agentic browsers resurfaces XSS- and CSRF-class harms",
 "class": "responsible_disclosure",
 "attack_surface": "browser_agent",
 "initial_vector": "indirect_prompt_injection_web_page",
 "agent_capability_abused": [
  "authenticated_session_reuse",
  "cross_site_navigation",
  "chat_context"
 ],
 "target_product": "Unnamed agentic browsers (vendors declined coordinated disclosure)",
 "target_vendor": null,
 "autonomy_level": "semi_autonomous",
 "impact_realized": false,
 "impact_type": [
  "data_exfiltration",
  "session_confusion",
  "persistence"
 ],
 "blast_radius": "Any data or service the user's browser can reach",
 "cve": [],
 "taxonomy": {
  "owasp_asi": [
   "ASI01",
   "ASI03"
  ],
  "mitre_atlas": [],
  "labels": [
   "browser_agent",
   "isolation",
   "xss_analogue",
   "csrf_analogue"
  ]
 },
 "defense_present": null,
 "defense_bypassed": true,
 "fix_shipped": null,
 "primary_sources": [
  "https://blog.trailofbits.com/2026/01/13/lack-of-isolation-in-agentic-browsers-resurfaces-old-vulnerabilities/"
 ],
 "verified_quote": "Without proper isolation, these agents can be exploited to compromise any data or service the user's browser can reach.",
 "confidence": "high",
 "notes": "Author Lucas Bourtoule. Eight attack classes in three groups (manipulation, data exfiltration, persistence). Products unnamed because the affected vendors declined coordinated disclosure; no CVEs.",
 "risk_category": "security_fraud",
 "risk_secondary": [
  "privacy"
 ],
 "risk_subcategory": "Prompt Injection",
 "risk_sub_secondary": [
  "Persistence & Covert C2"
 ],
 "ai_entity": "generative",
 "agency": "agent_acted",
 "agency_debatable": false,
 "agency_reason": "the agentic browsers reused authenticated sessions across origins",
 "vector_family": "indirect_prompt_injection",
 "vector_detail": "indirect_prompt_injection_web_page",
 "guardrail_kind": [
  "unknown"
 ],
 "guardrail_outcome": "silent",
 "xrefs": {
  "aiid": [],
  "atlas": [],
  "cve": [],
  "ghsa": []
 },
 "primary_asi": "ASI01",
 "agent_framework": "unknown",
 "model_provider": "unknown",
 "model_name": "",
 "detection_mechanism": "external_researcher",
 "tool_access": "unknown",
 "financial_loss_band": "unknown",
 "eai_category": "privilege_escalation",
 "eai_domain": "access_control_and_permissions",
 "eai_secondary": [
  "data_exfiltration_channels",
  "confused_deputy"
 ],
 "eai_reason": "impact rule: privilege_escalation",
 "asi_curated": [
  "ASI01"
 ],
 "asi_scope": "in_scope",
 "asi_provenance": "curated_plus_rule",
 "asi_reason": "curated: ASI01 | added ASI03 (signal=identity)",
 "submitted_by": "EAI Internal"
}