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.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-863"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56743.json"
}{
"extracted_events": [
{
"cpe": "cpe:2.3:a:cilium:cilium:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "1.19.0"
},
{
"fixed": "1.19.5"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "1c84ae3b58a7cd54f7ee355e6c524c82f620eae8"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "bacea640404c0805c23515353dc1681c5bf35171"
}
],
"source": "REFERENCES_COMMIT"
},
{
"original_tag": "v1.19.5",
"range": [
{
"fixed": "20eaccfef029cb046d70219717fb6dbbdf27a59f"
}
],
"source": "REFERENCES_TAG"
}
]
}