Bypass of namespace restrictions in CiliumNetworkPolicy
CVE-2023-41333

6.9MEDIUM

Key Information:

Vendor

Cilium

Status
Vendor
CVE Published:
27 September 2023

What is CVE-2023-41333?

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.

Affected Version(s)

cilium >= 1.14.0, < 1.14.2 < 1.14.0, 1.14.2

cilium >= 1.13.0, < 1.13.7 < 1.13.0, 1.13.7

cilium < 1.12.14 < 1.12.14

References

CVSS V3.1

Score:
6.9
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
Low
Attack Vector:
Adjacent Network
Attack Complexity:
Low
Privileges Required:
High
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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CVE-2023-41333 : Bypass of namespace restrictions in CiliumNetworkPolicy