{"id":"CVE-2026-77272","published":"2026-09-22T19:16:51.177","lastModified":"2026-09-28T13:10:43.460","description":"MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the OAuth error query parameter is passed to CallbackHandler._send_response in oauth_setup.py and interpolated into an HTML page without escaping. A crafted authorization callback can inject markup or script that executes in the browser of a user completing the OAuth flow. This issue is fixed in version 0.22.0.","cvssScore":5.4,"cvssSeverity":"MEDIUM","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N","cwes":["CWE-79"],"vendors":["mcp-atlassian"],"products":["mcp atlassian"],"references":[{"url":"https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460","tags":["Patch"]},{"url":"https://github.com/sooperset/mcp-atlassian/pull/1448","tags":["Issue Tracking","Patch"]},{"url":"https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0","tags":["Release Notes"]},{"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-g2r2-3j32-j27x","tags":["Exploit","Vendor Advisory"]}],"exploitRefs":[{"url":"https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460","tags":["Patch"]},{"url":"https://github.com/sooperset/mcp-atlassian/pull/1448","tags":["Issue Tracking","Patch"]},{"url":"https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0","tags":["Release Notes"]},{"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-g2r2-3j32-j27x","tags":["Exploit","Vendor Advisory"]}],"hasPoc":true,"ai":null}