Severity by source
AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Adjacent vector because exploitation requires a pod inside the cluster; PR:L because any standard workload suffices; S:C because the bypass escapes the policy boundary to affect peer workloads; no availability impact.
Primary rating from Vendor (GitHub_M).
CVSS VectorVendor: GitHub_M
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Lifecycle Timeline
3DescriptionCVE.org
Cilium is a networking, observability, and security solution. From 1.19.0 to 1.19.4, standard Kubernetes NetworkPolicy specifications using CIDR-based ipBlock rules without pod or namespace selectors erroneously generate a wildcard namespace allow rule when Cilium is configured with a custom clusterName rather than the default any value. The parser incorrectly instantiates a pod selector on selectorless peer definitions, allowing traffic from other workloads in the same namespace as the subject of the policy. This issue is fixed in version 1.19.5.
AnalysisAI
Network policy bypass in Cilium 1.19.0-1.19.4 allows workloads inside a Kubernetes namespace to reach peers that CIDR-based ipBlock NetworkPolicies should block. The flaw surfaces exclusively when Cilium is deployed with a custom clusterName (any value other than the default 'any'): the network-policy parser in parseNetworkPolicyPeer erroneously instantiates an empty pod selector for selectorless ipBlock peers, which compiles into a wildcard namespace-allow rule instead of a pure CIDR rule. …
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Three specific conditions must ALL be present simultaneously. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The provided CVSS 3.1 vector AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N yields a score of 5.4 (Medium), which is a reasonable reflection of real-world risk with important caveats. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker with the ability to deploy or compromise a pod in a Kubernetes namespace targets a service whose NetworkPolicy restricts inbound traffic to a specific external CIDR range via an ipBlock rule with no pod or namespace selectors. Because Cilium erroneously appends a wildcard intra-namespace allow rule, the attacker's pod can reach the target service over any port even though the policy should block intra-namespace traffic. … |
| Remediation | Upgrade Cilium to version 1.19.5, which contains the corrected parseNetworkPolicyPeer() logic in pkg/k8s/network_policy.go (commits 1c84ae3b58a7cd54f7ee355e6c524c82f620eae8 and bacea640404c0805c23515353dc1681c5bf35171). … Detailed patch versions, workarounds, and compensating controls in full report. |
Threat intelligence, references, and detailed analysis are available after sign-in.
More in Kubernetes
View allA critical vulnerability in Kubernetes ingress-nginx controller allows unauthenticated attackers with pod network access
Credential-harvesting malware compromised 84 versions of 42 TanStack npm packages on 2026-05-11 via chained GitHub Actio
Kubernetes ingress-nginx contains a configuration injection vulnerability via the mirror-target and mirror-host Ingress
A security issue was discovered in ingress-nginx https://github.com/kubernetes/ingress-nginx where the `auth-url` Ingres
A security issue was discovered in ingress-nginx https://github.com/kubernetes/ingress-nginx where the `auth-tls-match-c
Kubernetes API server in all versions allow an attacker who is able to create a ClusterIP service and set the spec.exter
Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. Rated critical severity (CVSS 9.9), this vulne
The Kubernetes integration in GitLab Enterprise Edition 11.x before 11.2.8, 11.3.x before 11.3.9, and 11.4.x before 11.4
Kyverno Kubernetes policy engine prior to 1.x has a privilege escalation vulnerability (CVSS 9.9) allowing policy bypass
Kamaji is the Hosted Control Plane Manager for Kubernetes. Rated critical severity (CVSS 9.9), this vulnerability is rem
Jumpserver is a popular open source bastion host, and Koko is a Jumpserver component that is the Go version of coco, ref
String filter bypass in Inspektor Gadget Kubernetes eBPF tooling before fix. Insufficient string escaping enables filter
Same weakness CWE-863 – Incorrect Authorization
View allSame technique Authentication Bypass
View allShare
External POC / Exploit Code
Leaving vuln.today
EUVD-2026-44774