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TI-2023-21933 Aliases CVE-2023-41333GHSA-4xp2-w642-7mcx

Bypass of namespace restrictions in CiliumNetworkPolicy

Priority LOW 36CWE-306Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
High
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-306.

Summary

Cilium is a networking, observability, and security solution with an eBPF-based dataplane. An attacker with the ability to create or modify CiliumNetworkPolicy objects in a particular namespace is able to affect traffic on an entire Cilium cluster, potentially bypassing policy enforcement in other namespaces. By using a crafted `endpointSelector` that uses the `DoesNotExist` operator on the `reserved:init` label, the attacker can create policies that bypass namespace restrictions and affect the entire Cilium cluster. This includes potentially allowing or denying all traffic. This attack requires API server access, as described in the Kubernetes API Server Attacker section of the Cilium Threat Model. This issue has been resolved in Cilium versions 1.14.2, 1.13.7, and 1.12.14. As a workaround an admission webhook can be used to prevent the use of `endpointSelectors` that use the `DoesNotExist` operator on the `reserved:init` label in CiliumNetworkPolicies.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00482 41st percentileScored 2026-11-07
Fix Fixed cilium (cilium): 1.14.2, 1.13.7, 1.12.14github.com/cilium/cilium (Go): 1.14.2, 1.13.7, 1.12.14

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
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
ciliumcilium1.14.0 to before 1.14.2; 1.13.0 to before 1.13.7; before 1.12.141.14.2, 1.13.7, 1.12.14Patch availableCNA
—github.com/cilium/cilium (Go)1.14.0 to before 1.14.21.14.2Patch availableGHSA-4xp2-w642-7mcx
—github.com/cilium/cilium (Go)1.13.0 to before 1.13.71.13.7Patch availableGHSA-4xp2-w642-7mcx
—github.com/cilium/cilium (Go)before 1.12.141.12.14Patch availableGHSA-4xp2-w642-7mcx
  • cilium Vendorcilium Affected 1.14.0 to before 1.14.2; 1.13.0 to before 1.13.7; before 1.12.14 Fixed in 1.14.2, 1.13.7, 1.12.14 Patch available CNA
  • github.com/cilium/cilium (Go) Vendor— Affected 1.14.0 to before 1.14.2 Fixed in 1.14.2 Patch available GHSA-4xp2-w642-7mcx
  • github.com/cilium/cilium (Go) Vendor— Affected 1.13.0 to before 1.13.7 Fixed in 1.13.7 Patch available GHSA-4xp2-w642-7mcx
  • github.com/cilium/cilium (Go) Vendor— Affected before 1.12.14 Fixed in 1.12.14 Patch available GHSA-4xp2-w642-7mcx

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:cilium:cilium:*:*:*:*:*:*:*:*before 1.12.14; 1.13.0 to before 1.13.7; 1.14.0 to before 1.14.2Vulnerablecilium
  • cpe:2.3:a:cilium:cilium:*:*:*:*:*:*:*:* Versions before 1.12.14; 1.13.0 to before 1.13.7; 1.14.0 to before 1.14.2 Vulnerable ·cilium

Remediation

  • Fix · CNA cilium (cilium) Fixed in 1.14.2, 1.13.7, 1.12.14
  • Fix · GHSA-4xp2-w642-7mcx github.com/cilium/cilium (Go) Fixed in 1.14.2 Advisory →
  • Fix · GHSA-4xp2-w642-7mcx github.com/cilium/cilium (Go) Fixed in 1.13.7 Advisory →
  • Fix · GHSA-4xp2-w642-7mcx github.com/cilium/cilium (Go) Fixed in 1.12.14 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-41333
  2. 2026-10-03 Alias added: GHSA-4xp2-w642-7mcx

References

Patch 2

Advisory 1

Other 2

  • TI-2024-32092 CIDR deny policies may not take effect when a more narrow CIDR allow is present CVSS 3.1HIGH 8.7
  • TI-2023-12305 Cilium eBPF filters may be temporarily removed during agent restart CVSS 3.1CRITICAL 9.8
  • TI-2023-20486 Cilium NetworkPolicy bypass via pod labels CVSS 3.1CRITICAL 9.0
  • TI-2022-11721 Incorrect Default Permissions in Cilium CVSS 3.1HIGH 8.8
  • TI-2026-36600 Cilium: Sensitive information disclosure and cluster disruption via local Envoy admin socket access CVSS 3.1CRITICAL 9.2
  • TI-2026-40915 Cilium: Namespaced HTTPRoutes can redirect traffic to other namespaces CVSS 3.1HIGH 8.9
See all 34 →

Sources

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