5.4Medium

CVE-2026-66781

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.

What this means for your business

An attacker can use it from inside the same network, without a login, and without anyone at your company clicking anything.
FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 18% of all known flaws.

What to do

1Ask your IT team or provider whether any of your systems use the affected product.
2If you do, follow the vendor's guidance. No patch reference has been published yet.

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CVE-2026-66781

What this means for your business

What to do

Not sure if your company is exposed to CVE-2026-66781?

Scoring

Dates

References