GitHub Advisoryadvisory · Go

GHSA-4hc4-pgfx-3mrx cilium-agent container can access the host via `hostPath` mount

MEDIUM Published 2023-03-17 Modified 2023-03-17 Official page ↗
Aliases
CVE-2023-27593
Ecosystem
Go
Packages
github.com/cilium/cilium
Severity
Moderate
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Weaknesses
CWE-276
Reviewed
2023-03-17

Affected packages

• Go github.com/cilium/cilium: < 1.11.15 → fixed in 1.11.15 • Go github.com/cilium/cilium: >= 1.12.0, < 1.12.8 → fixed in 1.12.8 • Go github.com/cilium/cilium: >= 1.13.0, < 1.13.1 → fixed in 1.13.1

Description

Impact 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. Patches The issue has been fixed and is available on versions >=1.11.15, >=1.12.8, >=1.13.1. Workarounds 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. References • PR containing resolution Acknowledgements The Cilium community has worked together with members of Isovalent and Form3 to prepare these mitigations. Special thanks to Anastasios Koutlis, Daniel Teixeira, and Magdalena Oczadly for their cooperation. For more information If you have any questions or comments about this advisory, please reach out on Slack. As usual, if you think you found a related vulnerability, we strongly encourage you to report security vulnerabilities to our private security mailing list: [email protected] - first, before disclosing them in any public forums. This is a private mailing list where only members of the Cilium internal security team are subscribed to, and is treated as top priority.

Related

Alias · CVE (1)

  • CVE-2023-27593 Cilium is a networking, observability, and security solution with an eBPF-based dataplane. vulnerability

Weakness · CWE (1)

  • CWE-276 Incorrect Default Permissions weakness

References