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TI-2025-34881 Aliases CVE-2025-55205GHSA-fcpm-6mxq-m5vv

Capsule tenant owners with "patch namespace" permission can hijack system namespaces label

Priority HIGH 72CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Required
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-863.

Summary

Capsule is a multi-tenancy and policy-based framework for Kubernetes. A namespace label injection vulnerability in Capsule v0.10.3 and earlier allows authenticated tenant users to inject arbitrary labels into system namespaces (kube-system, default, capsule-system), bypassing multi-tenant isolation and potentially accessing cross-tenant resources through TenantResource selectors. This vulnerability enables privilege escalation and violates the fundamental security boundaries that Capsule is designed to enforce. This vulnerability is fixed in 0.10.4.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0046 40th percentileScored 2026-11-07
Fix Fixed capsule (projectcapsule): 0.10.4github.com/projectcapsule/capsule (Go): 0.10.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
projectcapsulecapsulebefore 0.10.40.10.4Patch availableCNA
—github.com/projectcapsule/capsule (Go)before 0.10.40.10.4Patch availableGHSA-fcpm-6mxq-m5vv
  • capsule Vendorprojectcapsule Affected before 0.10.4 Fixed in 0.10.4 Patch available CNA
  • github.com/projectcapsule/capsule (Go) Vendor— Affected before 0.10.4 Fixed in 0.10.4 Patch available GHSA-fcpm-6mxq-m5vv

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:projectcapsule:capsule:*:*:*:*:*:*:*:*——projectcapsule
  • cpe:2.3:a:projectcapsule:capsule:*:*:*:*:*:*:*:* Versions — — ·projectcapsule

Remediation

  • Fix · CNA capsule (projectcapsule) Fixed in 0.10.4
  • Fix · GHSA-fcpm-6mxq-m5vv github.com/projectcapsule/capsule (Go) Fixed in 0.10.4 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-55205
  2. 2026-10-03 Alias added: GHSA-fcpm-6mxq-m5vv

References

Advisory 1

Other 4

  • TI-2024-26614 Capsule tenant owner with "patch namespace" permission can hijack system namespaces CVSS 3.1HIGH 8.8
  • TI-2026-18364 Capsule TenantResource RawItems Cluster-Scoped Resource Creation Vulnerability CVSS 4.0MEDIUM 6.9
  • TI-2026-44157 Capsule: Tenant owner bypasses Capsule's forbidden namespace/service/node label and annotation enforcement CVSS 3.1HIGH 7.1
  • TI-2026-46911 Improper input validation in projectcapsule capsule CVSS 3.1MEDIUM 6.8
  • TI-2026-44232 Capsule: Malformed ForbiddenAnnotations.Regex can bypass Tenant validation and trigger namespace admission panic CVSS 3.1MEDIUM 6.8
  • TI-2026-46912 Improper privilege management in projectcapsule capsule CVSS 3.1MEDIUM 6.6
See all 11 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences