CVE-2023-27595

Cilium eBPF filters may be temporarily removed during agent restart

State
Published
Severity
6.5 Medium
Published
Mar 17, 2023
Updated
Feb 25, 2025
Reserved
Mar 4, 2023

Read the record on cve.org

Description

Cilium is a networking, observability, and security solution with an eBPF-based dataplane. In version 1.13.0, when Cilium is started, there is a short period when Cilium eBPF programs are not attached to the host. During this period, the host does not implement any of Cilium's featureset. This can cause disruption to newly established connections during this period due to the lack of Load Balancing, or can cause Network Policy bypass due to the lack of Network Policy enforcement during the window. This vulnerability impacts any Cilium-managed endpoints on the node (such as Kubernetes Pods), as well as the host network namespace (including Host Firewall). This vulnerability is fixed in Cilium 1.13.1 or later. Cilium releases 1.12.x, 1.11.x, and earlier are not affected. There are no known workarounds.

Scores

CVSSScoreVectorSource
3.16.5 MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:LGitHub_M

Weaknesses

  • CWE-755 Improper Handling of Exceptional Conditions

Affected Products

ProductVersions
ciliumcilium
  • = 1.13.0Affected

References

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