{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-77255", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-08-20T19:02:23.417Z", "datePublished": "2026-09-22T18:29:20.167Z", "dateUpdated": "2026-09-22T18:29:20.167Z"}, "containers": {"cna": {"title": "MCP Atlassian: Arbitrary File Read & Exfiltration (Confused Deputy) in JIRA update_issue", "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-441", "lang": "en", "description": "CWE-441: Unintended Proxy or Intermediary ('Confused Deputy')", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 8.6, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-2xj6-xx86-cwwc", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-2xj6-xx86-cwwc"}, {"name": "https://github.com/sooperset/mcp-atlassian/pull/1448", "tags": ["x_refsource_MISC"], "url": "https://github.com/sooperset/mcp-atlassian/pull/1448"}, {"name": "https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460", "tags": ["x_refsource_MISC"], "url": "https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460"}, {"name": "https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0", "tags": ["x_refsource_MISC"], "url": "https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0"}], "affected": [{"vendor": "sooperset", "product": "mcp-atlassian", "versions": [{"version": "< 0.22.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-09-22T18:29:20.167Z"}, "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 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."}], "source": {"advisory": "GHSA-2xj6-xx86-cwwc", "discovery": "UNKNOWN"}}}}