diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 9cb99d14..61d2face 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -15,22 +15,22 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8  # v5.0.0
       with:
         fetch-depth: 0
     - name: Set up JDK 17
-      uses: actions/setup-java@v3
+      uses: actions/setup-java@dded0888837ed1f317902acf8a20df0ad188d165  # v5.0.0
       with:
         distribution: 'temurin'
         java-version: 17
     - name: Cache SonarCloud packages
-      uses: actions/cache@v3
+      uses: actions/cache@0400d5f644dc74513175e3cd8d07132dd4860809  # v4.2.4
       with:
         path: ~/.sonar/cache
         key: ${{ runner.os }}-sonar
         restore-keys: ${{ runner.os }}-sonar
     - name: Cache Maven packages
-      uses: actions/cache@v3
+      uses: actions/cache@0400d5f644dc74513175e3cd8d07132dd4860809  # v4.2.4
       with:
         path: ~/.m2
         key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }}
diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index 7a126a25..55694a49 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -9,15 +9,15 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8  # v5.0.0
       with:
         fetch-depth: 0
-    - uses: actions/setup-java@v3
+    - uses: actions/setup-java@dded0888837ed1f317902acf8a20df0ad188d165  # v5.0.0
       with:
         distribution: 'temurin'
         java-version: 11
     - name: Cache Maven packages
-      uses: actions/cache@v3
+      uses: actions/cache@0400d5f644dc74513175e3cd8d07132dd4860809  # v4.2.4
       with:
         path: ~/.m2
         key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }}
@@ -26,7 +26,7 @@ jobs:
       run: mvn javadoc:javadoc
 
     - name: Deploy docs
-      uses: peaceiris/actions-gh-pages@v3
+      uses: peaceiris/actions-gh-pages@4f9cc6602d3f66b9c108549d475ec49e8ef4d45e  # v4.0.0
       with:
         github_token: ${{ secrets.GITHUB_TOKEN }}
         publish_dir: ./target/site/apidocs