{"action":"Upgrade mcp to 1.27.2 or later.","affected":[{"fixed":"1.27.2","introduced":"1.23.0"}],"component":"mcp","cve_ids":["CVE-2026-52870"],"ecosystem":"PyPI","epss":0.00388,"exploited":false,"fixed_versions":["1.27.2"],"ghsa_id":"GHSA-hvrp-rf83-w775","id":"tcs_01M5KH5JV1MT3YXQX1RECCGRR7","modified_at":"2026-07-23T15:00:13.878977054Z","published_at":"2026-07-23T11:41:46.409906Z","references":["https://osv.dev/vulnerability/PYSEC-2026-3481","https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-hvrp-rf83-w775","https://nvd.nist.gov/vuln/detail/CVE-2026-52870","https://github.com/modelcontextprotocol/python-sdk/pull/2720","https://github.com/modelcontextprotocol/python-sdk/commit/62137874ff26dd74d2fea80ff528a7fd9ca7a5e7","https://github.com/modelcontextprotocol/python-sdk","https://github.com/modelcontextprotocol/python-sdk/releases/tag/v1.27.2","https://pypi.org/project/mcp","https://github.com/advisories/GHSA-hvrp-rf83-w775"],"severity":{"label":"high","score":7.6},"sources":[{"source":"osv","source_id":"PYSEC-2026-3481","url":"https://osv.dev/vulnerability/PYSEC-2026-3481"}],"summary":"MCP Python SDK: Experimental task handlers allow any client to access and cancel other clients' tasks"}