{"action":"Upgrade mcp/sdk to 0.7.1 or later.","affected":[{"fixed":"0.7.1","introduced":"0.5.0"}],"component":"mcp/sdk","cve_ids":["CVE-2026-53965"],"ecosystem":"Packagist","epss":0.00615,"exploited":false,"fixed_versions":["0.7.1"],"ghsa_id":"GHSA-7m52-jw36-44r3","id":"tcs_01M5KEY6QK99E9KTH3S3XK62D9","modified_at":"2026-08-19T19:33:55.087416Z","published_at":"2026-08-19T19:17:49Z","references":["https://osv.dev/vulnerability/GHSA-7m52-jw36-44r3","https://github.com/modelcontextprotocol/php-sdk/security/advisories/GHSA-7m52-jw36-44r3","https://github.com/FriendsOfPHP/security-advisories/blob/master/mcp/sdk/CVE-2026-53965.yaml","https://github.com/modelcontextprotocol/php-sdk","https://github.com/modelcontextprotocol/php-sdk/releases/tag/v0.7.1"],"severity":{"label":"medium","score":6.9},"sources":[{"source":"osv","source_id":"GHSA-7m52-jw36-44r3","url":"https://osv.dev/vulnerability/GHSA-7m52-jw36-44r3"},{"source":"nvd","source_id":"CVE-2026-53965","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53965"}],"summary":"MCP PHP SDK: client HttpTransport SSE buffer (sseBuffer .= chunk) grows unbounded when server withholds the event delimiter"}