Capsule: Incomplete fix of CVE-2026-30963: singular/plural typo leaves namespaces/finalize unprotected (CVE-2026-55636) | HOL Guard CVE

Medium severityCVE-2026-55636GHSA-GWXR-7H77-7777

Capsule: Incomplete fix of CVE-2026-30963: singular/plural typo leaves namespaces/finalize unprotected

Answer in brief

CVE-2026-55636 records a Medium severity vulnerability in Capsule: Incomplete fix of CVE-2026-30963: singular/plural typo leaves namespaces/finalize unprotected. The current sources do not mark it as known exploited. The current feed maps projectcapsule/capsule (generic), github.com/projectcapsule/capsule (go). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 15, 2026Updated Sep 15, 2026Source checked Sep 17, 2026First seen by HOL Jun 19, 2026Material review Sep 15, 2026

Upstream Advisory

Key facts

Risk: Medium
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps projectcapsule/capsule (generic), github.com/projectcapsule/capsule (go). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
projectcapsule/capsulegeneric	>= 0.13.0, < 0.13.6	Not reported
github.com/projectcapsule/capsulego	>=0.13.0,<0.13.6	0.13.6

Recommended response

Check inventory. Check lockfiles and deployed manifests for projectcapsule/capsule, github.com/projectcapsule/capsule.
Review the reported fix. Update github.com/projectcapsule/capsule to 0.13.6 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 15, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 15, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Jun 19, 2026

Sources and claim methodology

Upstream source description

Capsule is a multi-tenancy and policy-based framework for Kubernetes. From 0.13.0 until 0.13.6, charts/capsule/templates/configuration.yaml configures the validating webhook with namespace/finalize instead of the Kubernetes resource name namespaces/finalize. A user with namespaces/finalize RBAC can send a PUT request to /api/v1/namespaces/{namespace}/finalize, and the singular rule never matches the plural resource, so the validating webhook is not invoked and the user can change the namespace tenant label. matchPolicy: Equivalent does not compensate because it handles API group and version equivalence rather than resource-name errors. This vulnerability is fixed in 0.13.6.

Quoted source text, attributed separately from HOL analysis.