{"id":"CVE-2026-77265","title":"MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira)","summary":"MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, header-supplied Jira or Confluence URLs are resolved and validated before the HTTP client resolves the hostname again f…","severity":"medium","cvss":5.9,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","cwe":["CWE-918"],"vendor":"sooperset","product":"mcp-atlassian","affected":["mcp-atlassian < 0.22.0"],"published":"2026-09-22","updated":"2026-09-22","sourceUpdated":"2026-09-22T18:17:18.647","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-77265","references":[{"url":"https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460","label":"security-advisories@github.com"},{"url":"https://github.com/sooperset/mcp-atlassian/pull/1448","label":"security-advisories@github.com"},{"url":"https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0","label":"security-advisories@github.com"},{"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-49xv-9743-pw8w","label":"security-advisories@github.com"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-77265"},{"url":"https://github.com/advisories/GHSA-49xv-9743-pw8w"}],"tags":["nvd","cve.org","ghsa","pip"],"ingestedAt":"2026-09-22T18:08:12.486Z","aliases":["GHSA-49xv-9743-pw8w"],"ecosystem":"pip","patched":["mcp-atlassian 0.22.0"],"slug":"CVE-2026-77265","body":"## Overview\n\nMCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, header-supplied Jira or Confluence URLs are resolved and validated before the HTTP client resolves the hostname again for the connection. An unauthenticated caller can use a DNS-rebinding hostname that returns a public address during validation and an internal address during connection, causing requests to internal or metadata services. The advisory traces the vulnerable input and processing flow through X-Atlassian-Jira-Url, X-Atlassian-Confluence-Url, validate_url_for_ssrf, and DNS rebinding, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-77265)\n\nAffected packages:\n\n- `mcp-atlassian < 0.22.0`\n\nPatched in:\n\n- `mcp-atlassian 0.22.0`\n\nSource: https://github.com/advisories/GHSA-49xv-9743-pw8w","depth":"sunlit","depthScore":32,"depthScoreParts":{"impact":32.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}