{"id":"CVE-2026-77246","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, an HTTP transport deployment with READ_ONLY_MODE=false accepts a request without an Authorization identity and permits …","severity":"high","cvss":7.4,"cvssVector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","cwe":["CWE-22","CWE-200","CWE-441"],"vendor":"sooperset","product":"mcp-atlassian","affected":["mcp-atlassian < 0.22.0"],"published":"2026-09-22","updated":"2026-09-22","sourceUpdated":"2026-09-22T19:16:48.730","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-77246","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-wv8v-v4c5-v75j","label":"security-advisories@github.com"},{"url":"https://github.com/advisories/GHSA-wv8v-v4c5-v75j"}],"tags":["nvd","cve.org","ghsa","pip"],"ingestedAt":"2026-09-22T19:09:09.999Z","aliases":["GHSA-wv8v-v4c5-v75j"],"ecosystem":"pip","patched":["mcp-atlassian 0.22.0"],"slug":"CVE-2026-77246","body":"## Overview\n\nMCP 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-77246)\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-wv8v-v4c5-v75j","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":40.7,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}