- 6.9MediumCVSS base score
- 0.48%Exploitation in 30 daysEPSS · top 58% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Cilium is a networking, observability, and security solution with an eBPF-based dataplane. An attacker with the ability to create or modify CiliumNetworkPolicy objects in a particular namespace is able to affect traffic on an entire Cilium cluster, potentially bypassing policy enforcement in other namespaces. By using a crafted `endpointSelector` that uses the `DoesNotExist` operator on the `reserved:init` label, the attacker can create policies that bypass namespace restrictions and affect the entire Cilium cluster. This includes potentially allowing or denying all traffic. This attack requires API server access, as described in the Kubernetes API Server Attacker section of the Cilium Threat Model. This issue has been resolved in Cilium versions 1.14.2, 1.13.7, and 1.12.14. As a workaround an admission webhook can be used to prevent the use of `endpointSelectors` that use the `DoesNotExist` operator on the `reserved:init` label in CiliumNetworkPolicies.
Timeline
ID reserved
By GitHub_M
- 29 days later
· 29 days later
Published
- 12 months later
· 12 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium6.9 | CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:C/C:L/I:N/A:H |
| NVDNVD · Modified | 3.1 | High8.1 | CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.48% · top 58% of all CVEs (11 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.9.
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/cilium/ciliumGHSA-4xp2-w642-7mcx (opens in a new tab)
References
References3
- https://github.com/cilium/cilium/security/advisories/GHSA-4xp2-w642-7mcx (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/cilium/cilium/pull/28007 (opens in a new tab)x_refsource_MISCx_transferred
- https://docs.cilium.io/en/stable/security/threat-model/#kubernetes-api-server-attacker (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2023-2423 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-4xp2-w642-7mcx (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2023-41333)Record last updated .