projectcapsule Capsule up to 0.13.6 Hostname Validation hostname_regex.go hostnameRegexHandler.OnUpdate behavioral workflow

Summaryinfo

A vulnerability marked as problematic has been reported in projectcapsule Capsule up to 0.13.6. Impacted is the function hostnameRegexHandler.OnUpdate of the file internal/webhook/tenant/validation/hostname_regex.go of the component Hostname Validation. The manipulation leads to behavioral workflow. This vulnerability is documented as CVE-2026-61795. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in projectcapsule Capsule up to 0.13.6. This issue affects the function hostnameRegexHandler.OnUpdate of the file internal/webhook/tenant/validation/hostname_regex.go of the component Hostname Validation. The manipulation with an unknown input leads to a behavioral workflow vulnerability. Using CWE to declare the problem leads to CWE-841. The product supports a session in which more than one behavior must be performed by an actor, but it does not properly ensure that the actor performs the behaviors in the required sequence. Impacted is availability. The summary by CVE is:

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.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-61795 since 07/10/2026. The exploitation is known to be easy. The attack may be initiated remotely. The exploitation needs additional levels of successful authentication. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

Upgrading to version 0.13.7 eliminates this vulnerability.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Project Management Software

Vendor

• projectcapsule

Name

• Capsule

Version

• 0.13.0
• 0.13.1
• 0.13.2
• 0.13.3
• 0.13.4
• 0.13.5
• 0.13.6

Website

• Product: https://github.com/projectcapsule/capsule/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Discussion