CVE-2026-61795mediumCWE-697

CVE-2026-61795: medium-severity vulnerability in projectcapsule capsule

Capsule: hostnameRegexHandler.OnUpdate validates stale (old) Tenant regex, allowing invalid AllowedHostnames regex to bypass webhook validation

Published · Updated

Follow this CVE+ Monitor capsule+ Monitor github.com/projectcapsule/capsule

E-mail alert when it lands in KEV, gets a public PoC or its score goes up.

13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.8epss 0.6%
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.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
Affected products
projectcapsule · capsule
Related CVEs — projectcapsule capsule

In the same product, most dangerous first.

CVE-2026-22872MEDIUMCapsule TenantResource RawItems Cluster-Scoped Resource Creation VulnerabilityEPSS 0.7%CVE-2026-61794MEDIUMCapsule: Malformed ForbiddenAnnotations.Regex can bypass Tenant validation and trigger namespace admission panicEPSS 0.6%CVE-2024-39690HIGHCapsule tenant owner with "patch namespace" permission can hijack system namespacesEPSS 0.5%CVE-2025-55205CRITICALCapsule tenant owners with "patch namespace" permission can hijack system namespaces labelEPSS 0.5%CVE-2026-55636MEDIUMCapsule: Incomplete fix of CVE-2026-30963: singular/plural typo leaves namespaces/finalize unprotectedEPSS 0.4%CVE-2026-61672HIGHCapsule: Tenant owner bypasses Capsule's forbidden namespace/service/node label and annotation enforcementEPSS 0.3%