`gh attestation verify` returns incorrect exit code during verification if no attestations are present

Vulnerability Description

`gh` is GitHub’s official command line tool. Starting in version 2.49.0 and prior to version 2.67.0, under certain conditions, a bug in GitHub's Artifact Attestation cli tool `gh attestation verify` causes it to return a zero exit status when no attestations are present. This behavior is incorrect: When no attestations are present, `gh attestation verify` should return a non-zero exit status code, thereby signaling verification failure. An attacker can abuse this flaw to, for example, deploy malicious artifacts in any system that uses `gh attestation verify`'s exit codes to gatekeep deployments. Users are advised to update `gh` to patched version `v2.67.0` as soon as possible.

References

• https://github.com/cli/cli/security/advisories/GHSA-fgw4-v983-mgp8
• https://github.com/cli/cli/issues/10418
• https://github.com/cli/cli/pull/10421