diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index b3fd661..b980532 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -43,7 +43,7 @@ jobs:
 
         steps:
             - name: Checkout
-              uses: actions/checkout@v6
+              uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
 
             - name: Set up environment
               uses: ./.github/actions/setup
@@ -79,7 +79,7 @@ jobs:
 
         steps:
             - name: Checkout
-              uses: actions/checkout@v6
+              uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
 
             - name: Set up environment
               uses: ./.github/actions/setup
@@ -101,7 +101,7 @@ jobs:
 
         steps:
             - name: Checkout
-              uses: actions/checkout@v6
+              uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
 
             - name: Set up environment
               uses: ./.github/actions/setup
@@ -118,7 +118,7 @@ jobs:
 
         steps:
             - name: Checkout
-              uses: actions/checkout@v6
+              uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
               
             - name: Install SwiftLint
               run: brew install swiftlint