diff --git a/.github/workflows/untrustedPR.yml b/.github/workflows/untrustedPR.yml
index 895cd999efd68e..22ba597ddd6c97 100644
--- a/.github/workflows/untrustedPR.yml
+++ b/.github/workflows/untrustedPR.yml
@@ -38,8 +38,7 @@ jobs:
           git config user.email github-actions
           git config user.name github-actions@github.com
 
-          # HEAD^^ refers to the second parent of the merge commit
-          git diff --name-status --merge-base HEAD^^ HEAD --diff-filter=MAR -- '*portfile.cmake' | sed 's/[MAR]\t*//' | while read filename; do grep -s '(vcpkg_install_cmake|vcpkg_build_cmake|vcpkg_configure_cmake|vcpkg_fixup_cmake_targets)' "$filename" || echo " - \`$filename\`"; done > .github-pr.deprecated-cmake
+          git diff --name-status --merge-base HEAD^ HEAD --diff-filter=MAR -- '*portfile.cmake' | sed 's/[MAR]\t*//' | while read filename; do grep -q -E '(vcpkg_install_cmake|vcpkg_build_cmake|vcpkg_configure_cmake|vcpkg_fixup_cmake_targets)' "$filename" && echo " - \`$filename\`"; done > .github-pr.deprecated-cmake
           ./vcpkg format-manifest --all --convert-control
           git diff > .github-pr.format-manifest
           git add -u