diff --git a/.github/workflows/mend-slack.yml b/.github/workflows/mend-slack.yml
index f566734a9a43ed92de18954777433ecd07e15400..7dcc072d802df4015cfd82beacf8dbb3a3aef3c5 100644
--- a/.github/workflows/mend-slack.yml
+++ b/.github/workflows/mend-slack.yml
@@ -14,7 +14,7 @@ jobs:
     steps:
       - name: Post to Slack
         id: slack
-        uses: slackapi/slack-github-action@v1.24.0
+        uses: slackapi/slack-github-action@e28cf165c92ffef168d23c5c9000cffc8a25e117 # v1.24.0
         with:
           channel-id: 'C05NLTMGCJC'
           # For posting a simple plain text message