diff --git a/.github/workflows/invoke-push.yaml b/.github/workflows/invoke-push.yaml
index 16b775c2..8a232f94 100644
--- a/.github/workflows/invoke-push.yaml
+++ b/.github/workflows/invoke-push.yaml
@@ -16,14 +16,14 @@ jobs:
     environment: invoke-push
     steps:
       - name: Checkout self
-        uses: actions/checkout@v4
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5
         with:
           repository: G-Research/charts
           path: charts
           ref: master
       - run: npm i octokit @octokit/core
       - name: Trigger push workflow
-        uses: actions/github-script@v7
+        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b
         env:
           APP_ID: ${{ secrets.APP_ID }}
           APP_PRIVATE_KEY: ${{ secrets.APP_PRIVATE_KEY }}
diff --git a/.github/workflows/lint-test.yaml b/.github/workflows/lint-test.yaml
index 760cdb7e..cad297de 100644
--- a/.github/workflows/lint-test.yaml
+++ b/.github/workflows/lint-test.yaml
@@ -7,20 +7,20 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5
         with:
           fetch-depth: 0
 
       - name: Set up Helm
-        uses: azure/setup-helm@v4
+        uses: azure/setup-helm@1a275c3b69536ee54be43f2070a358922e12c8d4
 
-      - uses: actions/setup-python@v5
+      - uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065
         with:
           python-version: '3.9'
           check-latest: true
 
       - name: Set up chart-testing
-        uses: helm/chart-testing-action@v2.6.1
+        uses: helm/chart-testing-action@e6669bcd63d7cb57cb4380c33043eebe5d111992
 
       - name: Run chart-testing (list-changed)
         id: list-changed
@@ -42,7 +42,7 @@ jobs:
 
       - name: Create kind cluster
         if: steps.list-changed.outputs.changed == 'true'
-        uses: helm/kind-action@v1.9.0
+        uses: helm/kind-action@99576bfa6ddf9a8e612d83b513da5a75875caced
 
       - name: Run chart-testing (install)
         if: steps.list-changed.outputs.changed == 'true'
diff --git a/.github/workflows/push.yaml b/.github/workflows/push.yaml
index 32b552a9..b9f8f37d 100644
--- a/.github/workflows/push.yaml
+++ b/.github/workflows/push.yaml
@@ -34,12 +34,12 @@ jobs:
     environment: push
     steps:
       - name: Checkout self
-        uses: actions/checkout@v4
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5
         with:
           path: self
 
       - name: Validate chart
-        uses: actions/github-script@v7
+        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b
         env:
           APP_ID: ${{ secrets.APP_ID }}
           APP_PRIVATE_KEY: ${{ secrets.GH_APP_PEM }}
@@ -49,20 +49,20 @@ jobs:
             return await config({ core, context })
 
       - name: Checkout gh-pages
-        uses: actions/checkout@v4
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5
         with:
           ref: gh-pages
           path: gh-pages
 
       - name: Checkout ${{ env.OWNER }}/${{ env.REPO }}
-        uses: actions/checkout@v4
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5
         with:
           repository: ${{ env.OWNER }}/${{ env.REPO }}
           ref: ${{ env.REF }}
           path: source
 
       - name: Package charts
-        uses: actions/github-script@v7
+        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b
         with:
           script: |
             const helm = require('./self/.github/workflows/scripts/packageChart.js')
@@ -72,7 +72,7 @@ jobs:
         run: npm i octokit fs @octokit/core
 
       - name: Update index and push files
-        uses: actions/github-script@v7
+        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b
         env:
           APP_ID: ${{ secrets.APP_ID }}
           APP_PRIVATE_KEY: ${{ secrets.GH_APP_PEM }}