{"id":"CVE-2026-77246","revision":"20f59d0c85964dd19b784f1e6350559d","records":[{"revision":"20f59d0c85964dd19b784f1e6350559d","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-77246","aliases":[],"title":"MCP Atlassian: MCP HTTP Client Server-Local File Exfiltration via Unvalidated Attachment Upload Path","description":"MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, an HTTP transport deployment with READ_ONLY_MODE=false accepts a request without an Authorization identity and permits attacker-controlled Atlassian service headers, including X-Atlassian-Confluence-Url, to select a public attacker hostname or one allowed by MCP_ALLOWED_URL_DOMAINS. A caller can then invoke confluence_upload_attachment or the Jira attachment variant in src/mcp_atlassian/jira/attachments.py with a server-local file_path and cause the MCP process to send the file to the selected attachment endpoint. This issue is fixed in version 0.22.0.","state":0,"publishedAt":"2026-09-22T18:51:54.54+00:00","modifiedAt":"2026-09-24T15:26:33.55+00:00","affected":[{"ecosystem":"Vendor product","name":"mcp-atlassian","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"sooperset\",\n                    \"product\": \"mcp-atlassian\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 0.22.0\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","score":7.4,"severity":"HIGH"}],"references":["https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-wv8v-v4c5-v75j","https://github.com/sooperset/mcp-atlassian/pull/1448","https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460","https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-77246","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-77246","identifiers":["CVE-2026-77246"]},"retained":false,"historicalAffected":[]}],"coverage":[]}