CVE-2023-27593
Prior to versions 1.11.15, 1.12.8, and 1.13.1, an attacker with access to a Cilium agent pod can write to `/opt/cni/bin` due to a `hostPath` mount of that directory in the agent pod.
Does this matter?
Lower severity and a low EPSS score (0.22%). Track it; it rarely justifies an emergency change on its own.
Description
Cilium is a networking, observability, and security solution with an eBPF-based dataplane. Prior to versions 1.11.15, 1.12.8, and 1.13.1, an attacker with access to a Cilium agent pod can write to `/opt/cni/bin` due to a `hostPath` mount of that directory in the agent pod. By replacing the CNI binary with their own malicious binary and waiting for the creation of a new pod on the node, the attacker can gain access to the underlying node. The issue has been fixed and the fix is available on versions 1.11.15, 1.12.8, and 1.13.1. Some workarounds are available. Kubernetes RBAC should be used to deny users and service accounts `exec` access to Cilium agent pods. In cases where a user requires `exec` access to Cilium agent pods, but should not have access to the underlying node, no workaround is possible.
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.22% probability · 12th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-276
- Affected
- cilium/cilium
- Source
- security-advisories@github.com
References
- https://github.com/cilium/cilium/pull/24075Third Party Advisory
- https://github.com/cilium/cilium/releases/tag/v1.11.15Third Party Advisory
- https://github.com/cilium/cilium/releases/tag/v1.12.8Third Party Advisory
- https://github.com/cilium/cilium/releases/tag/v1.13.1Third Party Advisory
- https://github.com/cilium/cilium/security/advisories/GHSA-4hc4-pgfx-3mrxThird Party Advisory
- https://kubernetes.io/docs/reference/access-authn-authz/rbac/Third Party Advisory
- https://github.com/cilium/cilium/pull/24075Third Party Advisory
- https://github.com/cilium/cilium/releases/tag/v1.11.15Third Party Advisory
- https://github.com/cilium/cilium/releases/tag/v1.12.8Third Party Advisory
- https://github.com/cilium/cilium/releases/tag/v1.13.1Third Party Advisory
- https://github.com/cilium/cilium/security/advisories/GHSA-4hc4-pgfx-3mrxThird Party Advisory
- https://kubernetes.io/docs/reference/access-authn-authz/rbac/Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.