diff --git a/.github/workflows/publish-server-image.yml b/.github/workflows/publish-server-image.yml
index dedea74..791958c 100644
--- a/.github/workflows/publish-server-image.yml
+++ b/.github/workflows/publish-server-image.yml
@@ -256,9 +256,23 @@ jobs:
             grep -Fqx "$want" <<< "$platforms" || { echo "$first_tag is missing $want" >&2; exit 1; }
           done
           echo "digest=$(docker buildx imagetools inspect "$first_tag" --format '{{.Manifest.Digest}}')" >> "$GITHUB_OUTPUT"
-      # GitHub artifact attestations are unavailable for private repos on personal accounts.
+      # Owner type is not exposed on the github context; resolve it from the repository metadata API.
+      - name: Resolve registry attestation eligibility
+        id: attestation
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          set -euo pipefail
+          owner_type="$(gh api "repos/${GITHUB_REPOSITORY}" --jq -r '.owner.type')"
+          private="$(gh api "repos/${GITHUB_REPOSITORY}" --jq -r '.private')"
+          if [[ "$owner_type" == "User" && "$private" == "true" ]]; then
+            echo "enabled=false" >> "$GITHUB_OUTPUT"
+            echo "Skipping registry attestation: unavailable for private repositories on personal accounts."
+          else
+            echo "enabled=true" >> "$GITHUB_OUTPUT"
+          fi
       - name: Attest the published image
-        if: github.event.repository.private != true || github.repository_owner_type != 'User'
+        if: steps.attestation.outputs.enabled == 'true'
         uses: actions/attest-build-provenance@4d101475d8b20a2381f78447822ac1eab6504dd8 # v4.2.2
         with:
           subject-name: ghcr.io/${{ steps.ns.outputs.repo }}/${{ matrix.name }}
diff --git a/infra/updater/src/publish-workflow.test.ts b/infra/updater/src/publish-workflow.test.ts
index f75de81..4c9e292 100644
--- a/infra/updater/src/publish-workflow.test.ts
+++ b/infra/updater/src/publish-workflow.test.ts
@@ -38,12 +38,14 @@ describe("server image publish workflow", () => {
     expect(publish.needs).toBe("build");
     expect(workflowText).toContain("push-by-digest=true");
     expect(workflowText).toContain("docker buildx imagetools create");
-    expect(workflowText).toContain('if [[ "${#sources[@]}" -ne 1 ]]');
+    expect(workflowText).toContain(`if [[ "\${#sources[@]}" -ne 1 ]]`);
     expect(workflowText).toContain("for want in linux/amd64; do");
     expect(workflowText).toContain("actions/attest-build-provenance@");
-    expect(workflowText).toContain(
-      "if: github.event.repository.private != true || github.repository_owner_type != 'User'",
-    );
+    expect(workflowText).not.toContain("github.repository_owner_type");
+    expect(workflowText).toContain(`gh api "repos/\${GITHUB_REPOSITORY}"`);
+    expect(workflowText).toContain(".owner.type");
+    expect(workflowText).toContain("if: steps.attestation.outputs.enabled == 'true'");
+    expect(workflowText).toContain('[[ "$owner_type" == "User" && "$private" == "true" ]]');
   });
 
   it("stores digest markers under RUNNER_TEMP so self-hosted runners do not leak stale files", () => {
@@ -52,11 +54,11 @@ describe("server image publish workflow", () => {
   });
 
   it("names every image under the lowercase repository namespace", () => {
-    expect(workflowText).not.toContain("ghcr.io/${{ github.repository }}");
+    expect(workflowText).not.toContain(`ghcr.io/\${{ github.repository }}`);
     const references =
       workflowText.match(/ghcr\.io\/\$\{\{ steps\.ns\.outputs\.repo \}\}\//g) ?? [];
     expect(references.length).toBeGreaterThanOrEqual(6);
-    expect(workflowText).toContain("repo=${GITHUB_REPOSITORY,,}");
+    expect(workflowText).toContain(`repo=\${GITHUB_REPOSITORY,,}`);
   });
 
   it("keeps pull requests read-only and every action pinned to a commit", () => {