CVEvulnerability

CVE-2026-39884

8.1 HIGH Published 2026-04-15 Modified 2026-10-26 Official page ↗
Status
Analyzed
Published
2026-04-15
Last modified
2026-10-26
Assigner
[email protected]
CVSS 3.1 ([email protected])
8.3 HIGH — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L
CVSS 3.1 ([email protected])
8.1 HIGH — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Weaknesses
CWE-88

Description

mcp-server-kubernetes is a Model Context Protocol server for Kubernetes cluster management. Versions 3.4.0 and prior contain an argument injection vulnerability in the port_forward tool in src/tools/port_forward.ts, where a kubectl command is constructed via string concatenation with user-controlled input and then naively split on spaces before being passed to spawn(). Unlike all other tools in the codebase which correctly use array-based argument passing with execFileSync(), port_forward treats every space in user-controlled fields (namespace, resourceType, resourceName, localPort, targetPort) as an argument boundary, allowing an attacker to inject arbitrary kubectl flags. This enables exposure of internal Kubernetes services to the network by injecting --address=0.0.0.0, cross-namespace targeting by injecting additional -n flags, and indirect exploitation via prompt injection against AI agents connected to the MCP server. This issue has been fixed in version 3.5.0.

Affected configurations

• suyogs mcp-server-kubernetes (< 3.5.0)

Related

Weakness · CWE (1)

  • CWE-88 Improper Neutralization of Argument Delimiters in a Command weakness

References