{"id":"CVE-2026-77255","revision":"fe3bc9ec581b47fa9a4dc453d0941095","records":[{"revision":"fe3bc9ec581b47fa9a4dc453d0941095","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-77255","aliases":[],"title":"MCP Atlassian: Arbitrary File Read & Exfiltration (Confused Deputy) in JIRA update_issue","description":"MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the Jira update_issue attachments argument is converted into local paths and routed to the attachment upload implementation without workspace validation. A caller can make the MCP server read arbitrary local files and attach them to a Jira issue, using the server as a confused deputy to exfiltrate the contents. The advisory traces the vulnerable input and processing flow through jira update_issue, attachments, upload_attachment, and file_path, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.","state":0,"publishedAt":"2026-09-22T18:29:20.167+00:00","modifiedAt":"2026-09-26T00:00:47.513+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:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","score":8.6,"severity":"HIGH"}],"references":["https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-2xj6-xx86-cwwc","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-2026-77255","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-77255","identifiers":["CVE-2026-77255"]},"retained":false,"historicalAffected":[]}],"coverage":[]}