diff --git a/.changeset/promote-image-ecr-cosign-refs.md b/.changeset/promote-image-ecr-cosign-refs.md
new file mode 100644
index 000000000..84ff955a5
--- /dev/null
+++ b/.changeset/promote-image-ecr-cosign-refs.md
@@ -0,0 +1,56 @@
+---
+"promote-image-ecr": minor
+---
+
+Stop passing skopeo transport URLs to cosign.
+
+The action copies with `cosign copy`, but the script still built image references
+in skopeo's form, `docker://<registry>/<repo>:<tag>`. cosign parses references
+with go-containerregistry, which reads everything before the first `/` as the
+registry: it took `docker:` as the host and tried to reach `https://docker/v2/`,
+so every promotion failed on DNS before a registry was contacted.
+
+    Error: Get "https://docker/v2/": dial tcp: lookup docker on 127.0.0.53:53: server misbehaving
+
+This affected both the single-image and the images-matrix paths, and every
+released version, so no promotion this action ran has ever succeeded.
+
+The rest is the remainder of the same unfinished skopeo-to-cosign migration.
+
+`copy-signatures` is removed. It was documented as a switch to skopeo, but no
+skopeo path exists and the script never read the value, so setting it to `false`
+did not change what the action did. `cosign copy` always carries signatures and
+attestations. No caller in the org passes it.
+
+`SKOPEO_ARGS` and the `SRC_PASS`/`DST_PASS` environment variables are removed
+from the copy step. `SKOPEO_ARGS` was populated from `inputs.skopeo-additional-args`,
+an input this action does not declare, so it always expanded to empty. The two
+passwords were what skopeo's `--creds` flags needed; cosign authenticates from
+the Docker config that `amazon-ecr-login` writes, and nothing read them. They no
+longer enter the step environment.
+
+Three fixes to the images-matrix path, which was unusable beyond the reference
+bug above:
+
+- The loop read from a pipe, so it ran in a subshell. Its `IMAGE_COUNT` was
+  discarded and the run always reported `All 0 images copied successfully!`,
+  and the failure `exit 1` left the subshell rather than the script. It now
+  reads from a process substitution.
+- `sed -i "4i\"` is rejected by GNU sed as `i` with no text after it, so the
+  summary write failed once copying had succeeded. The total is now inserted by
+  rewriting the file. The heading it writes was `** Total Images Promoted:**`,
+  which Markdown does not render as bold; the stray space is gone.
+- `action.yaml` described the `images` objects with camelCase keys
+  (`sourceRepository`), while the script and the README both use snake_case
+  (`source_repository`). Following the documented casing produced nulls. The
+  description now matches.
+
+The `promoted-images` output returns the promotions it promised. It read
+`/tmp/promotion-results/promoted-images.json`, a file the script never writes;
+results land in `promotion-results.json`. The output was `[]` on every run,
+including successful ones. It now reads the `.promotions` array.
+
+The README's examples were not runnable: they passed underscore input names
+(`source_role_arn`) that the action does not declare, all of which are
+kebab-case, and pointed `uses:` at a local `./.github/actions/promote-image`
+path that does not exist in a consuming repo.
diff --git a/actions/promote-image-ecr/README.md b/actions/promote-image-ecr/README.md
index aa6ba8c5a..06c2b82cc 100644
--- a/actions/promote-image-ecr/README.md
+++ b/actions/promote-image-ecr/README.md
@@ -70,21 +70,19 @@ jobs:
       id-token: write
       contents: read
     steps:
-      - uses: actions/checkout@v4
-
       - name: Promote image
-        uses: ./.github/actions/promote-image
+        uses: smartcontractkit/.github/actions/promote-image-ecr@promote-image-ecr/0.5.0
         with:
-          source_aws_region: eu-west-1
-          destination_aws_region: us-east-1
-          source_role_arn: arn:aws:iam::111111111111:role/github-actions-ecr-read
-          destination_role_arn: arn:aws:iam::222222222222:role/github-actions-ecr-write
-          source_registry: 111111111111.dkr.ecr.eu-west-1.amazonaws.com
-          destination_registry: 222222222222.dkr.ecr.us-east-1.amazonaws.com
-          source_repository: my-app
-          destination_repository: my-app
-          source_tag: v1.0.0
-          destination_tag: v1.0.0
+          source-aws-region: eu-west-1
+          destination-aws-region: us-east-1
+          source-role-arn: arn:aws:iam::111111111111:role/github-actions-ecr-read
+          destination-role-arn: arn:aws:iam::222222222222:role/github-actions-ecr-write
+          source-registry: 111111111111.dkr.ecr.eu-west-1.amazonaws.com
+          destination-registry: 222222222222.dkr.ecr.us-east-1.amazonaws.com
+          source-repository: my-app
+          destination-repository: my-app
+          source-tag: v1.0.0
+          destination-tag: v1.0.0
 ```
 
 ### Multiple Images Promotion (Matrix)
@@ -101,17 +99,15 @@ jobs:
       id-token: write
       contents: read
     steps:
-      - uses: actions/checkout@v4
-
       - name: Promote multiple images
-        uses: ./.github/actions/promote-image
+        uses: smartcontractkit/.github/actions/promote-image-ecr@promote-image-ecr/0.5.0
         with:
-          source_aws_region: eu-west-1
-          destination_aws_region: us-east-1
-          source_role_arn: arn:aws:iam::111111111111:role/github-actions-ecr-read
-          destination_role_arn: arn:aws:iam::222222222222:role/github-actions-ecr-write
-          source_registry: 111111111111.dkr.ecr.eu-west-1.amazonaws.com
-          destination_registry: 222222222222.dkr.ecr.us-east-1.amazonaws.com
+          source-aws-region: eu-west-1
+          destination-aws-region: us-east-1
+          source-role-arn: arn:aws:iam::111111111111:role/github-actions-ecr-read
+          destination-role-arn: arn:aws:iam::222222222222:role/github-actions-ecr-write
+          source-registry: 111111111111.dkr.ecr.eu-west-1.amazonaws.com
+          destination-registry: 222222222222.dkr.ecr.us-east-1.amazonaws.com
           images: |
             [
               {
@@ -157,21 +153,19 @@ jobs:
           - { repo: "app2", tag: "v2.0.0" }
           - { repo: "service-x", tag: "sha-abc123" }
     steps:
-      - uses: actions/checkout@v4
-
       - name: Promote ${{ matrix.image.repo }}
-        uses: ./.github/actions/promote-image
+        uses: smartcontractkit/.github/actions/promote-image-ecr@promote-image-ecr/0.5.0
         with:
-          source_aws_region: eu-west-1
-          destination_aws_region: us-east-1
-          source_role_arn: arn:aws:iam::111111111111:role/github-actions-ecr-read
-          destination_role_arn: arn:aws:iam::222222222222:role/github-actions-ecr-write
-          source_registry: 111111111111.dkr.ecr.eu-west-1.amazonaws.com
-          destination_registry: 222222222222.dkr.ecr.us-east-1.amazonaws.com
-          source_repository: ${{ matrix.image.repo }}
-          destination_repository: ${{ matrix.image.repo }}
-          source_tag: ${{ matrix.image.tag }}
-          destination_tag: ${{ matrix.image.tag }}
+          source-aws-region: eu-west-1
+          destination-aws-region: us-east-1
+          source-role-arn: arn:aws:iam::111111111111:role/github-actions-ecr-read
+          destination-role-arn: arn:aws:iam::222222222222:role/github-actions-ecr-write
+          source-registry: 111111111111.dkr.ecr.eu-west-1.amazonaws.com
+          destination-registry: 222222222222.dkr.ecr.us-east-1.amazonaws.com
+          source-repository: ${{ matrix.image.repo }}
+          destination-repository: ${{ matrix.image.repo }}
+          source-tag: ${{ matrix.image.tag }}
+          destination-tag: ${{ matrix.image.tag }}
 ```
 
 ## Copy Tool
diff --git a/actions/promote-image-ecr/action.yaml b/actions/promote-image-ecr/action.yaml
index 16298d7ad..9ddea8680 100644
--- a/actions/promote-image-ecr/action.yaml
+++ b/actions/promote-image-ecr/action.yaml
@@ -1,6 +1,6 @@
 name: Promote image between ECR registries
 description: |
-  Promote an image from one ECR registry to another, using cosign (default) or skopeo.
+  Promote an image from one ECR registry to another, using cosign.
   The action will assume the provided IAM roles to access the source and destination registries.
 
 inputs:
@@ -55,17 +55,11 @@ inputs:
     required: false
   images:
     description: |
-      JSON array of images to promote. Each object should have: sourceRepository, destinationRepository, sourceTag, destinationTag.
-      Example: [{"sourceRepository":"app1","destinationRepository":"app1","sourceTag":"v1.0","destinationTag":"v1.0"}]
-      If provided, this takes precedence over individual sourceRepository/destinationRepository/sourceTag/destinationTag inputs.
+      JSON array of images to promote. Each object should have: source_repository, destination_repository, source_tag, destination_tag.
+      Example: [{"source_repository":"app1","destination_repository":"app1","source_tag":"v1.0","destination_tag":"v1.0"}]
+      If provided, this takes precedence over the individual source-repository/destination-repository/source-tag/destination-tag inputs.
     required: false
     default: ""
-  copy-signatures:
-    description:
-      Use cosign to copy images (includes signatures and attestations). Set to
-      'false' to use skopeo instead.
-    required: false
-    default: "true"
 
 outputs:
   promoted-images:
@@ -112,13 +106,9 @@ runs:
         SOURCE_TAG: ${{ inputs.source-tag }}
         DESTINATION_TAG: ${{ inputs.destination-tag }}
         IMAGES_JSON: ${{ inputs.images }}
-        SKOPEO_ARGS: ${{ inputs.skopeo-additional-args }}
         SOURCE_AWS_REGION: ${{ inputs.source-aws-region || inputs.aws-region }}
         DESTINATION_AWS_REGION:
           ${{ inputs.destination-aws-region || inputs.aws-region }}
-        SRC_PASS: ${{ steps.src.outputs.password }}
-        DST_PASS: ${{ steps.dst.outputs.password }}
-        COPY_SIGNATURES: ${{ inputs.copy-signatures }}
         ACTION_PATH: ${{ github.action_path }}
       run: |
         "${ACTION_PATH}/scripts/promote-images.sh"
@@ -144,8 +134,8 @@ runs:
       if: always()
       shell: bash
       run: |
-        if [ -f /tmp/promotion-results/promoted-images.json ]; then
-          echo "promoted-images=$(cat /tmp/promotion-results/promoted-images.json)" >> $GITHUB_OUTPUT
+        if [ -f /tmp/promotion-results/promotion-results.json ]; then
+          echo "promoted-images=$(jq -c '.promotions' /tmp/promotion-results/promotion-results.json)" >> $GITHUB_OUTPUT
         else
           echo "promoted-images=[]" >> $GITHUB_OUTPUT
         fi
diff --git a/actions/promote-image-ecr/scripts/promote-images.sh b/actions/promote-image-ecr/scripts/promote-images.sh
index fc76653b7..7ba9958bb 100755
--- a/actions/promote-image-ecr/scripts/promote-images.sh
+++ b/actions/promote-image-ecr/scripts/promote-images.sh
@@ -7,11 +7,13 @@ mkdir -p /tmp/promotion-results
 RESULTS_FILE="/tmp/promotion-results/promotion-summary.md"
 RESULTS_JSON="/tmp/promotion-results/promotion-results.json"
 
-echo "# Image Promotion Results" > "$RESULTS_FILE"
-echo "" >> "$RESULTS_FILE"
-echo "**Date:** $(date -u '+%Y-%m-%d %H:%M:%S UTC')" >> "$RESULTS_FILE"
-echo "**Copy Tool:** cosign" >> "$RESULTS_FILE"
-echo "" >> "$RESULTS_FILE"
+{
+  echo "# Image Promotion Results"
+  echo ""
+  echo "**Date:** $(date -u '+%Y-%m-%d %H:%M:%S UTC')"
+  echo "**Copy Tool:** cosign"
+  echo ""
+} > "$RESULTS_FILE"
 
 # Initialize JSON results
 echo '{"promotions": []}' > "$RESULTS_JSON"
@@ -41,21 +43,23 @@ write_markdown_result() {
   else
     emoji="❌"
   fi
-  echo "### $emoji ${repo}" >> "$RESULTS_FILE"
-  echo "" >> "$RESULTS_FILE"
-  echo "- **Source:** \`${repo}:${src_tag}\`" >> "$RESULTS_FILE"
-  echo "- **Destination:** \`${dst_repo}:${dst_tag}\`" >> "$RESULTS_FILE"
-  if [[ -n "$src_region" ]]; then
-    echo "- **Source Region:** \`${src_region}\`" >> "$RESULTS_FILE"
-  fi
-  if [[ -n "$dst_region" ]]; then
-    echo "- **Destination Region:** \`${dst_region}\`" >> "$RESULTS_FILE"
-  fi
-  if [[ "$status" == "success" ]]; then
-    echo "- **Duration:** ${duration}s" >> "$RESULTS_FILE"
-  fi
-  echo "- **Status:** ${status^}" >> "$RESULTS_FILE"
-  echo "" >> "$RESULTS_FILE"
+  {
+    echo "### $emoji ${repo}"
+    echo ""
+    echo "- **Source:** \`${repo}:${src_tag}\`"
+    echo "- **Destination:** \`${dst_repo}:${dst_tag}\`"
+    if [[ -n "$src_region" ]]; then
+      echo "- **Source Region:** \`${src_region}\`"
+    fi
+    if [[ -n "$dst_region" ]]; then
+      echo "- **Destination Region:** \`${dst_region}\`"
+    fi
+    if [[ "$status" == "success" ]]; then
+      echo "- **Duration:** ${duration}s"
+    fi
+    echo "- **Status:** ${status^}"
+    echo ""
+  } >> "$RESULTS_FILE"
 }
 
 # Function to append promotion result to JSON
@@ -88,19 +92,29 @@ write_promotion_json() {
 if [[ -n "$IMAGES_JSON" ]]; then
   # Process multiple images
   echo "Processing multiple images from matrix..."
-  echo "" >> "$RESULTS_FILE"
-  echo "## Promoted Images" >> "$RESULTS_FILE"
-  echo "" >> "$RESULTS_FILE"
+  {
+    echo ""
+    echo "## Promoted Images"
+    echo ""
+  } >> "$RESULTS_FILE"
+
+  if ! jq -e 'type == "array"' >/dev/null 2>&1 <<<"$IMAGES_JSON"; then
+    echo "::error::images input must be a JSON array"
+    exit 1
+  fi
 
+  # Read from a process substitution, not a pipe: a piped `while` runs in a
+  # subshell, so IMAGE_COUNT below would be discarded and the failure `exit 1`
+  # would leave the subshell rather than the script.
   IMAGE_COUNT=0
-  echo "$IMAGES_JSON" | jq -c '.[]' | while read -r image; do
+  while read -r image; do
     SRC_REPO=$(echo "$image" | jq -r '.source_repository')
     DST_REPO=$(echo "$image" | jq -r '.destination_repository')
     SRC_TAG=$(echo "$image" | jq -r '.source_tag')
     DST_TAG=$(echo "$image" | jq -r '.destination_tag')
 
-    SRC="docker://${SOURCE_REGISTRY}/${SRC_REPO}:${SRC_TAG}"
-    DST="docker://${DESTINATION_REGISTRY}/${DST_REPO}:${DST_TAG}"
+    SRC="${SOURCE_REGISTRY}/${SRC_REPO}:${SRC_TAG}"
+    DST="${DESTINATION_REGISTRY}/${DST_REPO}:${DST_TAG}"
 
     echo "-> Copying ${SRC} to ${DST}"
 
@@ -127,17 +141,22 @@ if [[ -n "$IMAGES_JSON" ]]; then
 
       exit 1
     fi
-  done
+  done < <(jq -c '.[]' <<<"$IMAGES_JSON")
   echo "----------------------------------------"
   echo "All ${IMAGE_COUNT} images copied successfully!"
 
-  # Add summary at the top
-  sed -i "3i\\** Total Images Promoted:** ${IMAGE_COUNT}" "$RESULTS_FILE"
-  sed -i "4i\\" "$RESULTS_FILE"
+  # Add the total just under the title block. Done by rewriting the file rather
+  # than with `sed -i "4i\\"`, which GNU sed rejects: `i` with nothing after it.
+  {
+    head -n 2 "$RESULTS_FILE"
+    echo "**Total Images Promoted:** ${IMAGE_COUNT}"
+    echo ""
+    tail -n +3 "$RESULTS_FILE"
+  } > "${RESULTS_FILE}.tmp" && mv "${RESULTS_FILE}.tmp" "$RESULTS_FILE"
 else
   # Process single image
-  SRC="docker://${SOURCE_REGISTRY}/${SOURCE_REPOSITORY}:${SOURCE_TAG}"
-  DST="docker://${DESTINATION_REGISTRY}/${DESTINATION_REPOSITORY}:${DESTINATION_TAG}"
+  SRC="${SOURCE_REGISTRY}/${SOURCE_REPOSITORY}:${SOURCE_TAG}"
+  DST="${DESTINATION_REGISTRY}/${DESTINATION_REPOSITORY}:${DESTINATION_TAG}"
 
   echo "-> Copying ${SRC} to ${DST}"