c4.3 Encrypt tool I/O and isolate tool sessions
Encrypt tool inputs, outputs, and execution context, and run each tool session in an isolated environment so state cannot leak between executions.
Implementation guidance
How to implement on AWS
Run tools on Amazon Bedrock AgentCore Runtime, whose dedicated microVMs isolate each session's CPU, memory, and file system and purge state on termination. Configure a customer managed KMS key for session data and require TLS 1.2+/AES-256 for all tool communications.
Acceptance criteria
Each session runs in an isolated microVM and purges state on completion; session data uses a customer managed key; tool traffic is TLS 1.2+.
Practical implementation
How this control is implemented in each reference architecture:
Tools run on AgentCore Runtime microVMs in the Generative AI account that isolate each session and purge state on termination, with session data CMK-encrypted and TLS in transit.
- Run tools on Amazon Bedrock AgentCore Runtime so each session gets a dedicated microVM isolating CPU, memory, and file system, with state purged on termination.
- Configure a customer managed KMS key for session data and require TLS 1.2+/AES-256 for all tool communications.
- Confirm no shared scratch space or cache persists across sessions.
How to validate: Each session runs in an isolated microVM and purges state on completion; session data uses the customer managed key; tool traffic is TLS 1.2+.
Avoid: Reusing one long-lived execution environment across users. Session state then leaks between users; isolate per session and purge on exit.
AgentCore Runtime microVMs isolate each tool session in the account and purge state on exit, with CMK-encrypted session data and TLS in transit.
- Run tools on AgentCore Runtime so each session is an isolated microVM that purges state on termination.
- Set a customer managed KMS key for session data and enforce TLS 1.2+/AES-256 on tool communications.
- Verify no cache or scratch space persists between sessions.
How to validate: Each session runs isolated and purges state; session data is CMK-encrypted; tool traffic is TLS 1.2+.
Avoid: Letting tools share a filesystem or memory across sessions. Isolate each session so one user's data cannot leak into another's tool run.
Threats addressed
- Data leakage between tool executions or user sessions.
- Tool inputs/outputs readable in transit or at rest.
AWS services
Framework mappings
OWASP GenAI/LLM Top 10 (2026)
- LLM02 Sensitive Information Disclosure
NIST AI Risk Management Framework (AI 100-1)
- MANAGE.1 AI risks are prioritized, responded to and managed
AWS Security Hub — AI Security Best Practices
- BedrockAgentCore.4 Bedrock AgentCore Gateway should be encrypted with customer managed AWS KMS keys
AWS Well-Architected Generative AI Lens (Security)
- GENSEC01-BP03 Implement least privilege access to data stores
OWASP GenAI Top 10 for Agentic Applications (2025)
- ASI06 Memory and Context Poisoning
Watch
Learning resources
References
- AWS SRA for AI — Capability 4, Data protection
AI Security Maturity Model