Detections
Analytics

SCA: security update for mcp-server-kubernetes (GHSA-4xqg-gf5c-ghwq)

high Tenable Cloud Security Plugin ID 440378

Description

There are packages installed that are affected by a vulnerability referenced in the following CVE:

 - 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. (CVE-2026-39884)

Solution

Update the mcp-server-kubernetes library and its related packages to version 3.5.0 or later.

See Also

https://github.com/advisories/GHSA-4xqg-gf5c-ghwq

Plugin Details

Severity: High

ID: 440378

Version: Revision 1.8

Type: Local

Family: SCA Checks

Published: 4/15/2026

Updated: 6/19/2026

Supported Sensors: Tenable Cloud Security, Tenable Self-Hosted Container Security

Risk Information

VPR

Risk Factor: Medium

Score: 4.3

Percentile: 53.59

Vendor

Vendor Severity: High

CVSS v2

Risk Factor: High

Base Score: 8.5

Temporal Score: 6.3

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:N

CVSS Score Source: CVE-2026-39884

CVSS v3

Risk Factor: High

Base Score: 8.1

Temporal Score: 7.1

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Exploit Ease: No known exploits are available

Patch Publication Date: 4/14/2026

Vulnerability Publication Date: 4/14/2026

Reference Information

CVE: CVE-2026-39884

cwe: CWE-88