CVE-2026-115419
Published:October 22, 2026
Updated:October 23, 2026
The A2A server component in Amazon Strands Agents SDK for Python before 1.43.0 and Amazon Strands Agents SDK for TypeScript before 1.5.0 does not properly isolate conversation state between callers. An authenticated remote user could read other tenants' conversation history and add persistent instructions that alter model behavior for subsequent callers via HTTP requests to the A2A endpoint using a different context_id.
To mitigate this issue, users should upgrade to strands-agents 1.43.0 (Python) or @strands-agents/sdk 1.5.0 (TypeScript).
Affected Packages
strands-agents (CONDA):
Affected version(s) >=1.4.0 <1.43.0Fix Suggestion:
Update to version 1.43.0https://github.com/strands-agents/harness-sdk.git (GITHUB):
Affected version(s) >=python/v1.0.0 <python/v1.43.0Fix Suggestion:
Update to version python/v1.43.0https://github.com/strands-agents/harness-sdk.git (GITHUB):
Affected version(s) >=typescript/v1.0.0 <typescript/v1.5.0Fix Suggestion:
Update to version typescript/v1.5.0@strands-agents/sdk (NPM):
Affected version(s) >=0.0.1 <1.5.0Fix Suggestion:
Update to version 1.5.0@strands-agents/sdk (NPM):
Affected version(s) >=1.0.0 <1.5.0Fix Suggestion:
Update to version 1.5.0strands-agents (PYTHON):
Affected version(s) >=1.0.0 <1.43.0Fix Suggestion:
Update to version 1.43.0strands-agents (PYTHON):
Affected version(s) >=0.0.1 <1.43.0Fix Suggestion:
Update to version 1.43.0Related Resources (15)
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Contact UsCVSS v4
Base Score:
8.6
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
8.1
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Exposure of Data Element to Wrong Session