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TI-2026-44157 Aliases CVE-2026-61672GHSA-gjw4-3v3v-rqxg

Capsule: Tenant owner bypasses Capsule's forbidden namespace/service/node label and annotation enforcement

Priority MEDIUM 64CWE-697Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
Security bypass
Confidentiality · integrity · availability
Low · High · None
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. Prior to 0.13.7, ForbiddenListSpec.ExactMatch in pkg/api/forbidden_list.go sorts denied metadata keys case-insensitively and then uses sort.SearchStrings, which assumes byte-order sorting. When an administrator's forbidden list mixes capitalized and lowercase keys or otherwise has different case-insensitive and byte ordering, the binary search can return false for a key that is present. An authenticated tenant owner can then pass the missed key through api.ValidateForbidden and bypass configured namespace, Service, or delegated node metadata restrictions, potentially influencing cluster policies, network exposure, or scheduling outside the tenant boundary. Uniformly lowercase lists whose two orderings coincide are not affected. This issue is fixed in version 0.13.7.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00334 26th percentileScored 2026-11-07
Fix Fixed capsule (projectcapsule): 0.13.7github.com/projectcapsule/capsule (Go): 0.13.7

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 0.13.70.13.7Patch availableCNA
—github.com/projectcapsule/capsule (Go)before 0.13.70.13.7Patch availableGHSA-gjw4-3v3v-rqxg
  • capsule Vendorprojectcapsule Affected before 0.13.7 Fixed in 0.13.7 Patch available CNA
  • github.com/projectcapsule/capsule (Go) Vendor— Affected before 0.13.7 Fixed in 0.13.7 Patch available GHSA-gjw4-3v3v-rqxg

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 0.13.7
  • Fix · GHSA-gjw4-3v3v-rqxg github.com/projectcapsule/capsule (Go) Fixed in 0.13.7 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-61672
  2. 2026-10-03 Alias added: GHSA-gjw4-3v3v-rqxg

References

Other 5

  • TI-2024-26614 Capsule tenant owner with "patch namespace" permission can hijack system namespaces CVSS 3.1HIGH 8.8
  • TI-2025-34881 Capsule tenant owners with "patch namespace" permission can hijack system namespaces label CVSS 3.1CRITICAL 9.1
  • TI-2026-18364 Capsule TenantResource RawItems Cluster-Scoped Resource Creation Vulnerability CVSS 4.0MEDIUM 6.9
  • 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