CVE-2026-115419High· 8.1▾ TwilightStrands Agents SDK: Exposure of data element to wrong session in the A2A Server
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 44.6 · likelihood 0.1 · exploitation 0
Need a working PoC? Pro members can cast a request and our team develops one — it lands right here.
Exploit-prediction probability, daily snapshots since Oct 23.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via OSV
0.3%
0.3% → 0.4%
Summary
Strands Agents SDK is an open-source SDK, available for Python (strands-agents) and TypeScript (@strands-agents/sdk), for building and running AI agents. An issue exists where, under certain circumstances, the Agent2Agent (A2A) server shares conversation history across callers with different context_id values, allowing one caller to read and influence another caller's session.
Impact
The A2A server did not properly isolate conversation state between callers. In multi-tenant deployments, an authenticated remote user could access another caller's conversation history or influence model behavior for other callers (CWE-488: Unintended Disclosure of Data Element to Wrong Session). This affects any deployment where an A2A server is reachable by more than one user or tenant.
Impacted versions:
strands-agents (Python): all versions containing the multiagent.a2a module, < 1.43.0
@strands-agents/sdk (TypeScript): < 1.5.0
Patches
This issue has been addressed in strands-agents version 1.43.0 and @strands-agents/sdk version 1.5.0. The A2A server now uses an agent factory so conversation state is isolated per A2A context_id. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes.
Workarounds
There is no workaround that fully addresses this issue in affected versions. Until you upgrade, do not expose an A2A server to more than one user or tenant. If multiple callers need access, run a separate A2A server instance for each user or tenant.
References
If you have any questions or comments about this advisory, we ask that you contact AWS Security via our vulnerability reporting page or directly via email to [email protected]. Please do not create a public GitHub issue.
strands-agents < 1.43.0@strands-agents/sdk < 1.5.0Upgrade to a patched release:
strands-agents 1.43.0@strands-agents/sdk 1.5.0Connected by shared product, vendor, weakness, or advisory.
GHSA-763v-5pjm-fx36MediumStrands Agents: Default FileSessionManager storage is world-readable on shared systems
GHSA-3w55-933p-8pv5High· 7.1Strands Agents: Local Privilege Escalation via Symlink Attack in Default Session File Storage
CVE-2026-82416High· 7.7FrankenPHP is a modern application server for PHP
CVE-2026-88017High· 7.3rclone is a command-line program to sync files and directories to and from different cloud storage providers
CVE-2026-114637High· 8.7Traefik v3.2.0 before v3.7.14 FastProxy NTLM/Negotiate Connection Pool Identity Leak
CVE-2026-112921NoneRobots::Validate versions from 0.4.3 before 0.4.10 for Perl report clients as imposter robots when User-Agent matcher state carries over from a previous request