Vulnerability Description
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, ENABLED_TOOLS and TOOLSETS are applied when tools are listed but are not rechecked when a tools/call request is dispatched. A client that knows a hidden tool name can directly invoke excluded read, write, or delete tools despite the operator's configured least-privilege restrictions. The advisory traces the vulnerable input and processing flow through ENABLED_TOOLS, TOOLSETS, tools/list, tools/call, and _call_tool_mcp, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Mcp-Atlassian | Mcp Atlassian | < 0.22.0 |
Related Weaknesses (CWE)
References
- https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c28Patch
- https://github.com/sooperset/mcp-atlassian/pull/1448Issue TrackingPatch
- https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0Release Notes
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-3r68-hf9h-88ExploitVendor Advisory
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-3r68-hf9h-88ExploitVendor Advisory
FAQ
What is CVE-2026-77243?
CVE-2026-77243 is a vulnerability with a CVSS score of 8.8 (HIGH). MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, ENABLED_TOOLS and TOOLSETS are applied when tools are listed but are not rechecked...
How severe is CVE-2026-77243?
CVE-2026-77243 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-77243?
Check the references section above for vendor advisories and patch information. Affected products include: Mcp-Atlassian Mcp Atlassian.