CVE-2023-27594

Cilium vulnerable to potential network policy bypass when routing IPv6 traffic

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, under specific conditions, Cilium may misattribute the source IP address of traffic to a cluster, identifying external traffic as coming from the host on which Cilium is running. As a consequence, network policies for that cluster might be bypassed, depending on the specific network policies enabled. This issue only manifests when Cilium is routing IPv6 traffic and NodePorts are used to route traffic to pods. IPv6 and endpoint routes are both disabled by default. The problem has been fixed and is available on versions 1.11.15, 1.12.8, and 1.13.1. As a workaround, disable IPv6 routing.

Categories

4.2
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.04%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: cilium cilium
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-27594?
CVE-2023-27594 has been scored as a medium severity vulnerability.
How to fix CVE-2023-27594?
To fix CVE-2023-27594, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-27594 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-27594 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-27594?
CVE-2023-27594 affects cilium cilium.
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