CVE-2026-115419

Unintended disclosure of data element to wrong session in Strands Agents SDK A2A Server

Published Oct 22, 2026 CVSS 4.0 · 8.6 High EPSS < 1% KEV · Not listed
Description
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).

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-4v6f-7vjh-6x4m Strands Agents SDK: Exposure of data element to wrong session in the A2A Server
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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).
Title Unintended disclosure of data element to wrong session in Strands Agents SDK A2A Server
First Time appeared Aws
Aws strands-agents
Aws strands-agents Sdk
Weaknesses CWE-488
CPEs cpe:2.3:a:aws:strands-agents:*:*:*:*:*:*:*:*
cpe:2.3:a:aws:strands-agents_sdk:*:*:*:*:*:*:*:*
Vendors & Products Aws
Aws strands-agents
Aws strands-agents Sdk
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N'}

cvssV4_0

{'score': 8.6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
AMZN
Published
Updated
Oct 30, 2026, 7:30 PM
Reserved
Oct 22, 2026, 1:19 PM
Status
Awaiting Analysis
Published
Oct 22, 2026, 9:17 PM
Modified
Oct 30, 2026, 8:17 PM