Medium (6.8). EPSS 0.6% chance of exploitation in the next 30 days. Fixed in github.com/projectcapsule/capsule 0.13.7.
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.
Severity
CVSS 3.1
6.8 medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
EPSS
0.6% chance of exploitation in the next 30 days; higher than 48% of CVEs (scores of 2026-10-31)