CVE-2026-77243

Name of the Vulnerable Software and Affected Versions MCP Atlassian versions prior to 0.22.0

Description An authorization bypass exists where the ENABLED TOOLS and TOOLSETS filters are only enforced during the tools/list request and are not re-verified when a tools/call request is dispatched. This allows a client who knows the name of a hidden tool to directly invoke excluded read, write, or delete operations, bypassing least-privilege restrictions. The issue occurs because the call tool mcp function resolves tools from the full unfiltered registry rather than the filtered list. This impact is most significant in multi-user HTTP-transport deployments where these filters serve as a trust boundary between clients.

Recommendations Update MCP Atlassian to version 0.22.0.