Resource exhaustion in Modelcontextprotocol Kotlin-Sdk
CVE-2026-108714
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 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.
Published .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- hackmd.io/@haind/mcp-kotlin-sdk-websocket-frame-allocation-dos (third-party-advisory)
- github.com/modelcontextprotocol/kotlin-sdk/blob/0.15.0/kotlin-sdk-server/src/co… (technical-description)
- github.com/modelcontextprotocol/kotlin-sdk/blob/0.15.0/kotlin-sdk-core/src/comm… (technical-description)
- github.com/modelcontextprotocol/kotlin-sdk (product)
- www.vulncheck.com/advisories/mcp-kotlin-sdk-through-0.15.0-memory-exhaustion-vi… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-108714?
- CVE-2026-108714 is a high-severity vulnerability in Modelcontextprotocol Kotlin-Sdk, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-10-11.
- How severe is CVE-2026-108714?
- High severity. CVSS v3 base score is 7.5 out of 10.