Log in Start free

Vulnerability · Published Aug 20, 2026 · Assigned by redhat

CVE-2026-66785Submariner: submariner: missing validation of remote endpoint subnets and clusterid enables cross-cluster traffic hijack

High 8.7

In plain English

A high-severity insufficient verification of data authenticity in Red Hat Advanced Cluster Management for Kubernetes 2 from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 11% of all known vulnerabilities).

Severity (CVSS 3.1)8.7High
Exploit odds (30 days)0.2%top 89.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

A flaw was found in Submariner. This vulnerability allows a malicious cluster (spoke) to redirect network traffic from other connected clusters (peer clusters) by publishing a specially crafted network endpoint. The system fails to properly validate the network subnets provided by the malicious cluster, enabling it to declare arbitrary network ranges. Consequently, all network traffic intended for these arbitrary ranges from peer clusters will be rerouted through the attacker's tunnel, potentially leading to unauthorized information disclosure or network disruption.

Affected products (as reported)

VendorProductVersions
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.16 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.16 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.16 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.16 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.16 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.16 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.16 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.17 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.17 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.17 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.17 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.17 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.17 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.17 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2 see references
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2 see references

Weakness: CWE-345 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N

References