CVE-2026-108714

MCP Kotlin SDK through 0.15.0 Memory Exhaustion via Application.mcpWebSocket

8.7 High

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.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: None
Integrity: None
Availability: High

Exploit likelihood

0.36%Unchanged since Oct 12, 2026

What each source reports

CVE List Score used 8.7

MCP Kotlin SDK through 0.15.0 Memory Exhaustion via Application.mcpWebSocket

Record: CVE-2026-108714
CVSS 4.0: 8.7 HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness: CWE-770
Updated: 2026-11-02

EUVDEUVD-2026-96988 8.7

Record: EUVD-2026-96988
CVSS 4.0: 8.7 HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Updated: 2026-11-02

GitHub AdvisoriesGHSA-645v-p22p-m3jx 8.7

MCP Kotlin SDK through 0.15.0 contains an uncontrolled memory allocation vulnerability that...

Record: GHSA-645v-p22p-m3jx
CVSS 4.0: 8.7 HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness: CWE-770
Updated: 2026-11-02

NVD 8.7

Record: CVE-2026-108714
CVSS 4.0: 8.7 HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness: CWE-770
Updated: 2026-11-02

OSV 8.7

MCP Kotlin SDK through 0.15.0 Memory Exhaustion via Application.mcpWebSocket

Record: CVE-2026-108714
CVSS 4.0: 8.7 HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Weakness: CWE-770
Updated: 2026-11-02

Affected products

modelcontextprotocol kotlin-sdk

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-108714 is a high vulnerability (CVSS 8.7) in Modelcontextprotocol Kotlin-sdk, published October 11, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.36%, the 29th percentile. No source names a fixed version.