Authorization Bypass in Kata Containers Affecting Security of Confidential Workloads

CVE-2026-64676

What is CVE-2026-64676?

The kata-agent in Kata Containers, an open-source implementation of lightweight Virtual Machines, is vulnerable to an authorization bypass related to the management of confidential guest memory in versions prior to 4.0.0. In deployments utilizing Confidential Containers (CoCo), this vulnerability arises from the failure of two new ttRPC methods, associated with the mem-agent feature, to enforce the crucial OPA/Rego-based AgentPolicy that governs API call authorization. As a result, if mem-agent is enabled (although it is disabled by default), an untrusted host can exploit this flaw, leading to unauthorized manipulation of in-guest memory management operations such as forced swapping and aggressive eviction. This vulnerability undermines the availability and performance of confidential workloads and circumvents established security policies. The issue is resolved in version 4.0.0.

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