CVE-2026-56743

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

15/07/2026

Last modified:

16/07/2026

Description

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.

Impact

Vector 3.x

CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N CVSS v3.1 Severity and Metrics:

Base Score: 5.40 MEDIUM
Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Attack Vector (AV): Adjacent
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Changed
Confidentiality (C): Low
Integrity (I): Low
Availability (A): None

Base Score 3.x

5.40

Severity 3.x

MEDIUM

CVE-2026-56743

Description

Impact

References to Advisories, Solutions, and Tools