CVE-2023-27595

Name: CVE-2023-27595
Creator: NVD / NIST
Published: 2023-03-17T22:15:11.317+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 0.73%

Last modified Jun 17, 2026

CVE-2023-27595 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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. EPSS estimates a 0.73% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

0.73%

49.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-755

Affected Software

Vendor	Product	Versions
Cilium	Cilium	1.13.0

References

https://github.com/cilium/cilium/pull/24336Third Party Advisory
https://github.com/cilium/cilium/releases/tag/v1.13.1Third Party Advisory
https://github.com/cilium/cilium/security/advisories/GHSA-r5x6-w42p-jhppThird Party Advisory
https://github.com/cilium/cilium/pull/24336Third Party Advisory
https://github.com/cilium/cilium/releases/tag/v1.13.1Third Party Advisory
https://github.com/cilium/cilium/security/advisories/GHSA-r5x6-w42p-jhppThird Party Advisory

Timeline

Published: Mar 17, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-27595?

How severe is CVE-2023-27595?

CVE-2023-27595 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 0.73% probability of exploitation in the next 30 days.

How do I fix CVE-2023-27595?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-27595?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST