CVE-2026-108714CWE-770denial-of-service

CVE-2026-108714

High · published October 11, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
28.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
EPSS
0.00358 · 28.3th percentile
Weakness
CWE-770 · Allocation of Resources Without Limits or Throttling
Published
2026-10-11T17:17Z
References (5)
https://github.com/modelcontextprotocol/kotlin-sdk · [email protected]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 · [email protected]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 · [email protected]https://hackmd.io/@haind/mcp-kotlin-sdk-websocket-frame-allocation-dos · [email protected]https://www.vulncheck.com/advisories/mcp-kotlin-sdk-through-0.15.0-memory-exhaustion-via-application-mcpwebsocket · [email protected]
EPSS history
Timeline
  • 13 OCT 03:28Z
    EPSS moved — → 0%
    epss
  • 11 OCT 12:19Z
    MCP Kotlin SDK through 0.15.0 Memory Exhaustion via Application.mcpWebSocket
    cvelistv5
  • 11 OCT 12:19Z
    MCP Kotlin SDK through 0.15.0 Memory Exhaustion via Application.mcpWebSocket
    cvelistv5