Sidero Labs signs the container images generated for the Talos release with cosign:
  • ghcr.io/siderolabs/installer (Talos installer)
  • ghcr.io/siderolabs/talos (Talos image for container runtime)
  • ghcr.io/siderolabs/talosctl (talosctl client packaged as a container image)
  • ghcr.io/siderolabs/imager (Talos install image generator)
  • all system extension images

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Verifying Container Image Signatures

The cosign tool can be used to verify the signatures of the Talos container images: 
$ cosign verify --certificate-identity-regexp '@siderolabs\.com$' --certificate-oidc-issuer https://accounts.google.com ghcr.io/siderolabs/installer:v1.4.0

Verification for ghcr.io/siderolabs/installer:v1.4.0 --
The following checks were performed on each of these signatures:
  - The cosign claims were validated
  - Existence of the claims in the transparency log was verified offline
  - The code-signing certificate was verified using trusted certificate authority certificates

[{"critical":{"identity":{"docker-reference":"ghcr.io/siderolabs/installer"},"image":{"docker-manifest-digest":"sha256:f41795cc88f40eb1bc6b3c638c4a3123f6ef3c90627bfc35c04ebab82581e3ee"},"type":"cosign container image signature"},"optional":{"1.3.6.1.4.1.57264.1.1":"https://accounts.google.com","Bundle":{"SignedEntryTimestamp":"MEQCIERkQpgEnPWnfjUHIWO9QxC9Ute3/xJOc7TO5GUnu59xAiBKcFvrDWHoUYChT0/+gaazTrI+r0/GWSbi+Q+sEQ5AKA==","Payload":{"body":"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","integratedTime":1681843022,"logIndex":18304044,"logID":"c0d23d6ad406973f9559f3ba2d1ca01f84147d8ffc5b8445c224f98b9591801d"}},"Issuer":"https://accounts.google.com","Subject":"andrey.smirnov@siderolabs.com"}}]
The image should be signed using cosign certificate authority flow by a Sidero Labs employee with and email from siderolabs.com domain.

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Reproducible Builds

Talos builds for kernel, initramfs, talosctl, ISO image, and container images are reproducible. So you can verify that the build is the same as the one as provided on GitHub releases page. See building Talos images for more details.