Auth bypass in Projectcapsule Capsule
CVE-2026-22872
Capsule is a multi-tenancy and policy-based framework for Kubernetes. The Capsule Controller runs with cluster-admin privileges. Although the TenantResource RawItems processing logic forcibly sets the namespace, this is ineffective for cluster-scoped resources. Prior to version 0.13.0, tenant administrators can leverage the Controller's elevated privileges to create cluster-scoped resources (such as ClusterRole and ValidatingWebhookConfiguration) that they cannot create directly, achieving cross-tenant privilege escalation and cluster-level attacks. The attack vector has a few limiting factors. This attack requires Tenant Owner privileges and requires Capsule Controller running with cluster-admin privileges (default configuration). Additionally, some clusters may have additional admission controllers blocking malicious resources. Version 0.13.0 patches this issue.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
EPSS: 0.007 (50.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H.
Affected products
- Projectcapsule Capsule — versions < 0.13.0
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
- security-advisories@github.com (Product, x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-22872?
- CVE-2026-22872 is a critical-severity vulnerability in Projectcapsule Capsule, classified under Improper Input Validation. CVSS score: 9.1/10. Published 2026-06-01.
- How severe is CVE-2026-22872?
- Critical severity. CVSS v3 base score is 9.1 out of 10.