diff --git a/.github/workflows/slsa-generator-nodejs-custom.yaml b/.github/workflows/slsa-generator-nodejs-custom.yaml
index 361c7c8..75b2286 100644
--- a/.github/workflows/slsa-generator-nodejs-custom.yaml
+++ b/.github/workflows/slsa-generator-nodejs-custom.yaml
@@ -27,7 +27,7 @@ jobs:
           PACKAGE_FILENAME=$(basename $PACKAGE_PATH)
           PACKAGE_NAME=$(jq -r '.name' package.json)
           PACKAGE_VERSION=$(jq -r '.version' package.json)
-          PACKAGE_INTEGRITY=$(shasum -a 512 $PACKAGE_PATH | awk '{print $1}')
+          PACKAGE_INTEGRITY=$(shasum -a 512 $PACKAGE_PATH | awk '{print $1}' | xxd -r -p | base64)
           echo "PACKAGE_FILENAME=${PACKAGE_FILENAME}" >> $GITHUB_OUTPUT
           echo "PACKAGE_NAME=${PACKAGE_NAME}" >> $GITHUB_OUTPUT
           echo "PACKAGE_VERSION=${PACKAGE_VERSION}" >> $GITHUB_OUTPUT