CVE-2025-55205

Capsule tenant owners with "patch namespace" permission can hijack system namespaces label

Published Aug 18, 2025 CVSS 3.1 · 9.1 Critical EPSS < 1% KEV · Not listed
Description
Capsule is a multi-tenancy and policy-based framework for Kubernetes. A namespace label injection vulnerability in Capsule v0.10.3 and earlier allows authenticated tenant users to inject arbitrary labels into system namespaces (kube-system, default, capsule-system), bypassing multi-tenant isolation and potentially accessing cross-tenant resources through TenantResource selectors. This vulnerability enables privilege escalation and violates the fundamental security boundaries that Capsule is designed to enforce. This vulnerability is fixed in 0.10.4.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
EUVD EUVD EUVD-2025-25141 Capsule tenant owners with "patch namespace" permission can hijack system namespaces label
Github GHSA Github GHSA GHSA-fcpm-6mxq-m5vv Capsule tenant owners with "patch namespace" permission can hijack system namespaces label
History
Type Values Removed Values Added
First Time appeared Projectcapsule
Projectcapsule capsule
Vendors & Products Projectcapsule
Projectcapsule capsule
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Capsule is a multi-tenancy and policy-based framework for Kubernetes. A namespace label injection vulnerability in Capsule v0.10.3 and earlier allows authenticated tenant users to inject arbitrary labels into system namespaces (kube-system, default, capsule-system), bypassing multi-tenant isolation and potentially accessing cross-tenant resources through TenantResource selectors. This vulnerability enables privilege escalation and violates the fundamental security boundaries that Capsule is designed to enforce. This vulnerability is fixed in 0.10.4.
Title Capsule tenant owners with "patch namespace" permission can hijack system namespaces label
Weaknesses CWE-863
References
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Aug 18, 2025, 5:39 PM
Reserved
Aug 8, 2025, 9:55 PM
Status
Deferred
Published
Aug 18, 2025, 5:15 PM
Modified
Jun 17, 2026, 9:41 AM