CVE-2026-66781
MediumCVSS 5.4Exploitation Probability (EPSS)
Low risk18th percentile - higher than 18% of all known CVEs
Summary
A flaw was found in the Submariner operator. The Submariner Custom Resource (CR), used for configuring network connectivity, stores the IPsec pre-shared key (PSK) in an unencrypted format. This key, which is critical for securing communication between Kubernetes clusters, can be accessed by unauthorized parties. Such access enables an attacker to passively decrypt network traffic flowing between any two clusters in the mesh, resulting in sensitive information disclosure.
Risk Assessment
Exposure of the PSK can allow an attacker to decrypt all traffic between clusters, leading to severe data confidentiality breach.
Recommendation
Secure the storage of the PSK, e.g., by using encryption or secret management, and restrict access to the CR resource.
Other vulnerabilities in Submariner
See all- CVE-2026-66786Critical
In Submariner's cert-auth mode, connection configuration is built from unvalidated free-form strings from the CRD. A malicious cluster can publish a CableName with newlines and ipsec.conf directives, allowing injection of arbitrary configuration or command execution via leftupdown hooks, leading to remote code execution as root on the gateway node.
- CVE-2026-66785Low
A vulnerability in Submariner allows a malicious cluster (spoke) to redirect network traffic from other connected clusters by publishing a specially crafted network endpoint. The system fails to properly validate network subnets, enabling the malicious cluster to declare arbitrary network ranges.
- CVE-2024-5042Medium
A flaw in the Submariner project involves unnecessary RBAC permissions. A privileged attacker can run a malicious container on a node, steal service account tokens, and compromise other nodes or the entire cluster.
Original NVD description (English source)
A flaw was found in the Submariner operator. The Submariner Custom Resource (CR), used for configuring network connectivity, stores the IPsec pre-shared key (PSK) in an unencrypted format. This key, which is critical for securing communication between Kubernetes clusters, can be accessed by unauthorized parties. Such access enables an attacker to passively decrypt network traffic flowing between any two clusters in the mesh, resulting in sensitive information disclosure.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS