Verify Signed Kubernetes Artifacts

FEATURE STATE: Kubernetes v1.26 [beta]

Before you begin

You will need to have the following tools installed:

Verifying binary signatures

The Kubernetes release process signs all binary artifacts (tarballs, SPDX files, standalone binaries) by using cosign's keyless signing. To verify a particular binary, retrieve it together with its signature and certificate:



for FILE in "${FILES[@]}"; do
    curl -sSfL --retry 3 --retry-delay 3 "$URL/$FILE" -o "$FILE"

Then verify the blob by using cosign verify-blob:

cosign verify-blob "$BINARY" \
  --signature "$BINARY".sig \
  --certificate "$BINARY".cert \
  --certificate-identity \

Verifying image signatures

For a complete list of images that are signed please refer to Releases.

Pick one image from this list and verify its signature using the cosign verify command:

cosign verify \
  --certificate-identity \
  --certificate-oidc-issuer \
  | jq .

Verifying images for all control plane components

To verify all signed control plane images for the latest stable version (v1.30.0), please run the following commands:

curl -Ls "$(curl -Ls" \
  | grep "SPDXID:" \
  | grep -v sha256 | cut -d- -f3- | sed 's/-/\//' | sed 's/-v1/:v1/' \
  | sort > images.txt
while IFS= read -r image
  cosign verify "$image" \
    --certificate-identity \
    --certificate-oidc-issuer \
    | jq .
done < "$input"

Once you have verified an image, you can specify the image by its digest in your Pod manifests as per this example:


For more information, please refer to the Image Pull Policy section.

Verifying Image Signatures with Admission Controller

For non-control plane images (for example conformance image), signatures can also be verified at deploy time using sigstore policy-controller admission controller.

Here are some helpful resources to get started with policy-controller:

Verify the Software Bill Of Materials

You can verify the Kubernetes Software Bill of Materials (SBOM) by using the sigstore certificate and signature, or the corresponding SHA files:

# Retrieve the latest available Kubernetes release version
VERSION=$(curl -Ls

# Verify the SHA512 sum
curl -Ls "$VERSION/release" -o "$VERSION.spdx"
echo "$(curl -Ls "$VERSION/release.sha512") $VERSION.spdx" | sha512sum --check

# Verify the SHA256 sum
echo "$(curl -Ls "$VERSION/release.sha256") $VERSION.spdx" | sha256sum --check

# Retrieve sigstore signature and certificate
curl -Ls "$VERSION/release.sig" -o "$VERSION.spdx.sig"
curl -Ls "$VERSION/release.cert" -o "$VERSION.spdx.cert"

# Verify the sigstore signature
cosign verify-blob \
    --certificate "$VERSION.spdx.cert" \
    --signature "$VERSION.spdx.sig" \
    --certificate-identity \
    --certificate-oidc-issuer \
Last modified December 24, 2023 at 9:00 PM PST: fix typos (d536e46dbd)