{"id":"CVE-2026-108714","title":"MCP Kotlin SDK through 0.15.0 contains an uncontrolled memory allocation vulnerability that allows remote clients to exhaust server memory because Application.mcpWebSocket installs Ktor WebSockets without a maxFrameSize limit","summary":"MCP Kotlin SDK through 0.15.0 contains an uncontrolled memory allocation vulnerability that allows remote clients to exhaust server memory because Application.mcpWebSocket installs Ktor WebSockets without a maxFrameSize limit. Attackers …","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-770"],"vendor":"modelcontextprotocol","product":"kotlin-sdk","affected":["kotlin-sdk <= 0.15.0"],"published":"2026-10-11","updated":"2026-10-16","sourceUpdated":"2026-10-16T19:18:44.867","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-108714","references":[{"url":"https://github.com/modelcontextprotocol/kotlin-sdk","label":"disclosure@vulncheck.com"},{"url":"https://github.com/modelcontextprotocol/kotlin-sdk/blob/0.15.0/kotlin-sdk-core/src/commonMain/kotlin/io/modelcontextprotocol/kotlin/sdk/shared/WebSocketMcpTransport.kt#L60-L85","label":"disclosure@vulncheck.com"},{"url":"https://github.com/modelcontextprotocol/kotlin-sdk/blob/0.15.0/kotlin-sdk-server/src/commonMain/kotlin/io/modelcontextprotocol/kotlin/sdk/server/WebSocketMcpKtorServerExtensions.kt#L41-L63","label":"disclosure@vulncheck.com"},{"url":"https://hackmd.io/@haind/mcp-kotlin-sdk-websocket-frame-allocation-dos","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/mcp-kotlin-sdk-through-0.15.0-memory-exhaustion-via-application-mcpwebsocket","label":"disclosure@vulncheck.com"}],"tags":["nvd","cve.org"],"epss":0.00358,"epssPercentile":0.29325,"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-10-14T13:22:52.401475Z"},"ingestedAt":"2026-10-11T13:51:17.025Z","slug":"CVE-2026-108714","body":"## Overview\n\nMCP Kotlin SDK through 0.15.0 contains an uncontrolled memory allocation vulnerability that allows remote clients to exhaust server memory because Application.mcpWebSocket installs Ktor WebSockets without a maxFrameSize limit. Attackers can send small frame headers declaring payloads near 2 GiB over one or a few connections, forcing huge heap allocations and causing denial of service.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}