diff --git a/.github/workflows/integration.yml b/.github/workflows/integration.yml
index 7f5556b7..eeda14a6 100644
--- a/.github/workflows/integration.yml
+++ b/.github/workflows/integration.yml
@@ -21,7 +21,7 @@ jobs:
 
     steps:
     - name: Check out VERDICT source
-      uses: actions/checkout@v3.6.0
+      uses: actions/checkout@v4.0.0
 
     - name: Set up GraphViz
       uses: ts-graphviz/setup-graphviz@v1
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index a742cc88..2a6c807c 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -26,7 +26,7 @@ jobs:
 
     steps:
     - name: Check out VERDICT source
-      uses: actions/checkout@v3.6.0
+      uses: actions/checkout@v4.0.0
 
     - name: Set up OCaml
       uses: ocaml/setup-ocaml@v2.0.19
@@ -85,7 +85,7 @@ jobs:
 
     - name: Check out VERDICT-update-sites
       if: runner.os == 'Linux'
-      uses: actions/checkout@v3.6.0
+      uses: actions/checkout@v4.0.0
       with:
         repository: ge-high-assurance/VERDICT-update-sites
         token: ${{ secrets.CI_PAT }}
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 2dcfe0bf..696a47c8 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -22,11 +22,11 @@ jobs:
 
     steps:
     - name: Check out VERDICT source
-      uses: actions/checkout@v3.6.0
+      uses: actions/checkout@v4.0.0
 
     - name: Check out kind2 source
       if: runner.os == 'macOS'
-      uses: actions/checkout@v3.6.0
+      uses: actions/checkout@v4.0.0
       with:
         repository: kind2-mc/kind2
         path: tools/verdict-back-ends/kind2
@@ -92,7 +92,7 @@ jobs:
 
     steps:
     - name: Check out VERDICT source
-      uses: actions/checkout@v3.6.0
+      uses: actions/checkout@v4.0.0
 
     - name: Set up GraphViz
       uses: ts-graphviz/setup-graphviz@v1
@@ -164,7 +164,7 @@ jobs:
           gehighassurance/verdict:${{ github.event.release.tag_name }}
 
     - name: Check out VERDICT-update-sites
-      uses: actions/checkout@v3.6.0
+      uses: actions/checkout@v4.0.0
       with:
         repository: ge-high-assurance/VERDICT-update-sites
         token: ${{ secrets.CI_PAT }}