Conversation
Signed-off-by: Radoslav Dimitrov <radoslav@stacklok.com>
Signed-off-by: Radoslav Dimitrov <radoslav@stacklok.com>
Signed-off-by: Radoslav Dimitrov <radoslav@stacklok.com>
JAORMX
approved these changes
Mar 16, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
The following PR fixes an issue where image verification fails with "image is not signed" for images signed with cosign v2+ using OCI 1.1 referrers (sigstore bundle v0.3) even though the signatures are valid.
The root cause is a go-containerregistry bug (google/go-containerregistry#1997) where the referrers fallback tag index sets
artifactTypetoapplication/vnd.oci.empty.v1+json(the config media type) instead of propagating the actual artifactTypefrom the inner manifest (application/vnd.dev.sigstore.bundle.v0.3+json). The existing filter inbundleFromAttestationonly checked the index descriptor'sartifactType`, causing it to skip all valid sigstore bundles.This change introduces an
isSigstoreBundlehelper that checks three sources: the index descriptor'sartifactType(fast path for compliant registries), the manifest'sconfig.ArtifactType, and the layer media types as a final fallback.