{"id":"CVE-2026-77244","published":"2026-09-22T18:17:17.560","lastModified":"2026-09-23T18:12:04.247","description":"MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the HTTP transport accepts requests without a verified user identity and downstream fetcher construction falls back to the operator's globally configured Jira or Confluence credentials. A network client that can reach the MCP endpoint can invoke Atlassian tools as the operator, including read and write operations available to that account. The advisory traces the vulnerable input and processing flow through UserTokenMiddleware, AtlassianOpaqueTokenVerifier, _get_fetcher, and streamable-http, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.","cvssScore":10,"cvssSeverity":"CRITICAL","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N","cwes":["CWE-287","CWE-303","CWE-862"],"vendors":[],"products":[],"references":[{"url":"https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460","tags":[]},{"url":"https://github.com/sooperset/mcp-atlassian/pull/1448","tags":[]},{"url":"https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0","tags":[]},{"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-wrhw-j3f9-8vc6","tags":[]}],"exploitRefs":[{"url":"https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460","tags":[]},{"url":"https://github.com/sooperset/mcp-atlassian/pull/1448","tags":[]},{"url":"https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0","tags":[]},{"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-wrhw-j3f9-8vc6","tags":[]}],"hasPoc":true,"ai":{"summary":"The flaw allows a network client to invoke Atlassian tools as the operator due to unverified user identity, posing a critical risk.","exploitability":"Exploitation is relatively easy if a network client can reach the MCP endpoint, requiring no user interaction.","blast_radius":"If exploited, this could result in unauthorized read and write operations on Atlassian Confluence and Jira tools, severely impacting data integrity and security.","remediation":"Upgrade to MCP Atlassian version 0.22.0 or later.","detection":"No reliable host or network indicator is derivable from the published description.","tags":["auth-bypass","web","atlassian","mcp"],"model":"qwen2.5:7b-instruct","analyzedAt":"2026-09-28T08:46:23.885Z"}}