Attestations for
  ghcr.io/boks-sh/xz-utils@sha256:15f04beb2a3c2aa6c4184b6f27ff41ba58c677c138268435bcd627353d502c9d

Verify them yourself:
  cosign verify-attestation --key cosign.pub \
      --type <cyclonedx|slsaprovenance> ghcr.io/boks-sh/xz-utils@sha256:15f04beb2a3c2aa6c4184b6f27ff41ba58c677c138268435bcd627353d502c9d

=== cyclonedx ===================================================
  (no attestation matches the document published now -- 0 older one(s) are attached)

=== slsaprovenance ==============================================
  (no attestation matches the document published now -- 0 older one(s) are attached)