{"id":"CVE-2026-77242","published":"2026-09-22T18:17:16.430","lastModified":"2026-09-23T18:28:25.093","description":"MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, validate_url_for_ssrf checks a hostname's resolved addresses, but Requests and urllib3 resolve the hostname again when connecting. A caller can use a short-lived DNS answer that is public during validation and private during connection, preserving unauthenticated access to internal or metadata endpoints despite the earlier CVE-2026-27826 remediation. The advisory traces the vulnerable input and processing flow through validate_url_for_ssrf, _check_dns_resolution, socket.getaddrinfo, and _make_ssrf_safe_hook, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.","cvssScore":7.5,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N","cwes":["CWE-367","CWE-918"],"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-72fm-whvq-jghf","tags":[]},{"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-72fm-whvq-jghf","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-72fm-whvq-jghf","tags":[]},{"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-72fm-whvq-jghf","tags":[]}],"hasPoc":true,"ai":null}