Authorization Flaw in mcp-server-kubernetes (CVE-2026-46519)
Summary
Vulnerability in mcp-server-kubernetes (CVE-2026-46519). Successful exploitation can lead to full system takeover. Exploitable via ALLOW_ONLY_READONLY_TOOLS. Mitigation: upgrade to 3.6.0 or later.
Original description
The description as published by the source.
mcp-server-kubernetes is a Model Context Protocol server for Kubernetes cluster management. Prior to version 3.6.0, mcp-server-kubernetes exposes three environment variables (ALLOW_ONLY_READONLY_TOOLS, ALLOW_ONLY_NON_DESTRUCTIVE_TOOLS, ALLOWED_TOOLS) documented as access controls for restricting which Kubernetes operations are available. These controls are enforced at the tool discovery layer (tools/list) but not at the execution layer (tools/call). Any client that knows a tool name can invoke it directly regardless of the configured restriction mode. The access control was effectively cosmetic. This issue has been patched in version 3.6.0.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-46519 has been found in mcp-server-kubernetes.
Attackers can target a specific entry point like ALLOW_ONLY_READONLY_TOOLS over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 8.8/10.
What to do: upgrade mcp-server-kubernetes to 3.6.0 or later.
If unsure, ask your IT team or search "mcp-server-kubernetes CVE-2026-46519" on the vendor's site.
CVE-2026-46519 (mcp-server-kubernetes) — CWE-863 / CVSS v3 8.8
Attack vector: remote (network-reachable) / no user interaction
Attack surface: ALLOW_ONLY_READONLY_TOOLS / ALLOW_ONLY_NON_DESTRUCTIVE_TOOLS / ALLOWED_TOOLS / kubectl_delete
Patched: 3.6.0 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Incorrect authorization (CWE-863) exists in mcp-server-kubernetes. Attackers reach the vulnerable code path via ALLOW_ONLY_READONLY_TOOLS.
Check the vendor advisory for the affected versions of mcp-server-kubernetes. Attack surface: ALLOW_ONLY_READONLY_TOOLS / ALLOW_ONLY_NON_DESTRUCTIVE_TOOLS / ALLOWED_TOOLS / kubectl_delete.
Severity: High (CVSS 8.8/10). Successful exploitation can lead to full system takeover.
Update to 3.6.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'mcp-server-kubernetes' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'mcp-server-kubernetes' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
mcp-server-kubernetesを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade mcp-server-kubernetes to 3.6.0ステージング環境で 3.6.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- web github.com
- web github.com