CVE-2026-61795
Capsule is a multi-tenancy and policy-based framework for Kubernetes. From 0.13.0 until 0.13.7, hostnameRegexHandler.OnUpdate in internal/webhook/tenant/validation/hostname_regex.go reverses the new and old Tenant parameters and validates the previous AllowedHostnames.Regex instead of the submitted value. A cluster administrator can therefore store a malformed AllowedHostnames.Regex after the webhook accepts the update based on stale valid state. Subsequent Ingress creation or update reaches validate_hostnames.go, which evaluates the malformed pattern, ignores the regular-expression error, and treats every hostname as unmatched, blocking Ingress operations for the affected tenant until an administrator repairs the Tenant configuration. This issue is fixed in version 0.13.7.
What this means for your business
- An attacker can use it remotely, over a network, with an administrator login, and without anyone at your company clicking anything.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 6.8 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H- Weakness
- CWE-697
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-18
- Last modified
- 2026-09-24
- Sources
- NVD