Kata Containers 4.3.1

4.3.1 is a patch release following 4.3.0, focused on keeping insecure CA certificates out of every guest image we ship. It also switches the NVIDIA CPU configurations to an uncompressed kernel and improves the agent's PCI mapping tests.

Security

Keep insecure CA certificates out of guest images

Some previously published guest images contain CA certificates affected by the eMudhra certificate incident, in which private keys are publicly known. Trusting those certificates poses a risk to TLS connections made from the guest, including networked Confidential Containers components.

#14110 checks every CA bundle that ends up in a guest image, and the build fails if a bundle still trusts AAA Certificate Services or emSign ECC Root CA - G3. Where the bundle comes from differs per image:

Ubuntu guest

The builder copies its CA bundle from the build environment and checks it before the copy. Ubuntu's updated ca-certificates package removes the affected certificates, so build with an updated build environment; the check rejects a stale bundle rather than removing certificates from it.

NVIDIA GPU guest

Reuses the Ubuntu bundle, and checks it again in the final image so that a cached build stage created before this release cannot carry it forward.

Devkit extension

Installs Ubuntu's ca-certificates package itself. It now also pulls from the -updates and -security pockets: the release pocket alone still ships the affected emSign ECC Root CA - G3 certificate.

Azure Linux guest

Gets its CA bundle from Azure Linux's ca-certificates package, which still trusts both certificates. The builder adds them to the guest's CA trust blocklist and regenerates the bundles, so the guest distrusts them until a fixed package is available.

Other changes

NVIDIA CPU configurations use an uncompressed kernel

Both the Go and runtime-rs NVIDIA CPU configurations now select the uncompressed NVIDIA kernel (#14087). These configurations do not use EDK2, so the compressed kernel required by the NVIDIA GPU configurations adds unnecessary decompression work at pod startup.

Independent PCI mapping tests

The agent's PCI device environment mapping tests now run as independent rstest cases, each starting from the same fixture. A failure identifies the scenario that broke without depending on state from an earlier case (#14101). This is a test-only refactor.

Upgrading

Follow the installation guide to deploy 4.3.1. Replace affected guest images and recreate running sandboxes so their guests use the updated CA bundle. Updating host packages alone does not replace the bundle inside an existing guest image or running VM. Rebuild custom guest images with an updated build environment as well.

The prerequisites and breaking changes documented for 4.3.0 still apply. This patch release introduces no additional configuration migration.

The changes since 4.3.0 are listed in the full changelog.