PT-2026-60282 · Cilium · Cilium

CVE-2026-56743 · Published 2026-07-15 · Updated 2026-07-19

Positive Technologies (AI Summary)

CVSS v3.1

5.4

Medium

Base vector

AV:A/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Name of the Vulnerable Software and Affected Versions Cilium versions 1.19.0 through 1.19.4

Description When configured with a custom clusterName instead of the default value, the parser incorrectly instantiates a pod selector on selectorless peer definitions. This occurs during the processing of standard Kubernetes NetworkPolicy specifications that use CIDR-based ipBlock rules without pod or namespace selectors, resulting in the erroneous generation of a wildcard namespace allow rule. Consequently, traffic from other workloads within the same namespace as the policy subject is permitted.

Recommendations Update to version 1.19.5.

Exploit

Fix

Incorrect Authorization

Weakness Enumeration

CWE-863

Related Identifiers

BIT-CILIUM-2026-56743

BIT-CILIUM-OPERATOR-2026-56743

BIT-HUBBLE-RELAY-2026-56743

CVE-2026-56743

GHSA-FM8W-2M5W-9J7R

Affected Products

Cilium

References · 12

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56743.json · Exploit
• https://github.com/cilium/cilium/security/advisories/GHSA-fm8w-2m5w-9j7r · Vendor Advisory
• https://github.com/cilium/cilium/pull/46305 · Patch
• https://github.com/cilium/cilium/commit/bacea640404c0805c23515353dc1681c5bf35171 · Patch
• https://github.com/cilium/cilium/commit/1c84ae3b58a7cd54f7ee355e6c524c82f620eae8 · Patch
• https://github.com/cilium/cilium/pull/46456 · Patch
• https://osv.dev/vulnerability/CVE-2026-56743 · Vendor Advisory
• https://osv.dev/vulnerability/BIT-hubble-relay-2026-56743 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-56743 · Security Note
• https://osv.dev/vulnerability/BIT-cilium-2026-56743 · Vendor Advisory
• https://osv.dev/vulnerability/BIT-cilium-operator-2026-56743 · Vendor Advisory
• https://github.com/cilium/cilium/releases/tag/v1.19.5 · Note