diff --git a/.github/workflows/build-linux-arm.yml b/.github/workflows/build-linux-arm.yml
index 50349b1c..21ff6aeb 100644
--- a/.github/workflows/build-linux-arm.yml
+++ b/.github/workflows/build-linux-arm.yml
@@ -45,7 +45,7 @@ jobs:
             cc: clang-15
 
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
     - name: Configure build
       working-directory: ${{ runner.temp }}
diff --git a/.github/workflows/build-linux.yml b/.github/workflows/build-linux.yml
index 0a0eda17..ef982128 100644
--- a/.github/workflows/build-linux.yml
+++ b/.github/workflows/build-linux.yml
@@ -49,7 +49,7 @@ jobs:
             ivf: ON
 
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
     - name: Install MKL
       timeout-minutes: 5
       run: |
diff --git a/.github/workflows/build-macos.yaml b/.github/workflows/build-macos.yaml
index 4af0ae0e..8445d32b 100644
--- a/.github/workflows/build-macos.yaml
+++ b/.github/workflows/build-macos.yaml
@@ -44,7 +44,7 @@ jobs:
             needs_prefix: true
 
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
     - name: Install Compiler
       run: |
diff --git a/.github/workflows/cibuildwheel.yml b/.github/workflows/cibuildwheel.yml
index bf8c58a5..2f9f5cc1 100644
--- a/.github/workflows/cibuildwheel.yml
+++ b/.github/workflows/cibuildwheel.yml
@@ -33,7 +33,7 @@ jobs:
     runs-on: ubuntu-22.04
 
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
     - name: Build Container
       run: |
diff --git a/.github/workflows/pre-commit.yml b/.github/workflows/pre-commit.yml
index 6a186f15..a48a2750 100644
--- a/.github/workflows/pre-commit.yml
+++ b/.github/workflows/pre-commit.yml
@@ -21,7 +21,7 @@ jobs:
   pre-commit:
     runs-on: ubuntu-24.04
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
     - uses: actions/setup-python@v6
       with:
         python-version: '3.12'