{"id":"CVE-2026-77271","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, validate_safe_path defaults its base directory to os.getcwd(), and affected Confluence attachment call sites omit base_…","severity":"high","cvss":8.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-22","CWE-94"],"vendor":"mcp-atlassian","product":"mcp_atlassian","affected":["mcp_atlassian < 0.22.0"],"patched":["mcp_atlassian 0.22.0"],"published":"2026-09-22","updated":"2026-09-28","sourceUpdated":"2026-09-28T13:45:34.133","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-77271","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-6vmq-24h2-pj7j","label":"security-advisories@github.com"},{"url":"https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-6vmq-24h2-pj7j","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-77271"},{"url":"https://github.com/advisories/GHSA-6vmq-24h2-pj7j"},{"url":"https://github.com/sooperset/mcp-atlassian"},{"url":"https://pypi.org/project/mcp-atlassian"}],"tags":["nvd","cve.org","exploit-available","ghsa","pip","osv"],"epss":0.00596,"epssPercentile":0.4828,"aliases":["GHSA-6vmq-24h2-pj7j","PYSEC-2026-4087"],"ecosystem":"pip","exploitAvailable":true,"ssvc":{"exploitation":"poc","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-24T14:27:52.995265Z"},"scores":{"nvd":8.8,"cna":8.3},"ingestedAt":"2026-09-22T19:09:09.987Z","slug":"CVE-2026-77271","body":"## Overview\n\nMCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, validate_safe_path defaults its base directory to os.getcwd(), and affected Confluence attachment call sites omit base_dir, allowing attacker-selected writes within the working directory. This Python module overwrite can provide code execution when the application later imports the modified module, bypassing the remediation tracked as CVE-2026-27825. This issue is fixed in version 0.22.0.\n\n## Affected\n\n- `mcp_atlassian < 0.22.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `mcp_atlassian 0.22.0`\n\n## Package advisory (CVE-2026-77271)\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-6vmq-24h2-pj7j","depth":"midnight","depthScore":61,"depthScoreParts":{"impact":48.4,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[{"seq":211933,"id":"CVE-2026-77271","ts":1790604773992,"field":"cvss","old":"8.3","new":"8.8"},{"seq":210181,"id":"CVE-2026-77271","ts":1790264793596,"field":"exploit_available","old":"false","new":"true"}]}