{"id":"CVE-2026-73496","state":"PUBLISHED","title":"MCP Atlassian: Arbitrary server-side file read via attachment upload","description":"MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the confluence_upload_attachment and confluence_upload_attachments tools pass a client-controlled file_path through src/mcp_atlassian/confluence/attachments.py upload_attachment, and the jira_update_issue attachments parameter reaches src/mcp_atlassian/jira/attachments.py upload_attachment, without confining either path to an approved server workspace. In a remote HTTP, SSE, or multi-user deployment, absolute or traversing paths are resolved on the MCP server and uploaded to Atlassian, allowing a client with write-tool access to disclose server files, environment-held Atlassian credentials, or another tenant's data. A local single-user stdio deployment does not cross this trust boundary because the server runs in the caller's environment. This issue is fixed in version 0.22.0.","publishedAt":"2026-09-14T19:49:03.525Z","updatedAt":"2026-09-16T16:10:16.281Z","severity":{"score":7.7,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["sooperset mcp-atlassian"],"affected":[{"vendor":"sooperset","product":"mcp-atlassian","versions":[{"version":"< 0.22.0","status":"affected"}]}],"references":["https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-wm45-qh3g-v83f","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"],"weaknesses":["CWE-22","CWE-73"],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/73xxx/CVE-2026-73496.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-73496","state":"PUBLISHED","datePublished":"2026-09-14T19:49:03.525Z","dateUpdated":"2026-09-16T16:10:16.281Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-08-12T19:00:33.735Z"},"containers":{"cna":{"title":"MCP Atlassian: Arbitrary server-side file read via attachment upload","descriptions":[{"lang":"en","value":"MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the confluence_upload_attachment and confluence_upload_attachments tools pass a client-controlled file_path through src/mcp_atlassian/confluence/attachments.py upload_attachment, and the jira_update_issue attachments parameter reaches src/mcp_atlassian/jira/attachments.py upload_attachment, without confining either path to an approved server workspace. In a remote HTTP, SSE, or multi-user deployment, absolute or traversing paths are resolved on the MCP server and uploaded to Atlassian, allowing a client with write-tool access to disclose server files, environment-held Atlassian credentials, or another tenant's data. A local single-user stdio deployment does not cross this trust boundary because the server runs in the caller's environment. This issue is fixed in version 0.22.0."}],"affected":[{"vendor":"sooperset","product":"mcp-atlassian","versions":[{"version":"< 0.22.0","status":"affected"}]}],"references":[{"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-wm45-qh3g-v83f","name":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-wm45-qh3g-v83f","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/sooperset/mcp-atlassian/pull/1448","name":"https://github.com/sooperset/mcp-atlassian/pull/1448","tags":["x_refsource_MISC"]},{"url":"https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460","name":"https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460","tags":["x_refsource_MISC"]},{"url":"https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0","name":"https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":7.7,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"NONE","privilegesRequired":"LOW","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-22","lang":"en","description":"CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-73","lang":"en","description":"CWE-73: External Control of File Name or Path","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-09-14T19:49:03.525Z"},"source":{"advisory":"GHSA-wm45-qh3g-v83f","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-wm45-qh3g-v83f","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-16T16:09:47.067461Z","id":"CVE-2026-73496","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-16T16:10:16.281Z"}}]}}}