diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6b1ae54c..7983a912 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,10 +13,10 @@ jobs:
     runs-on: ubuntu-24.04
 
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
 
     - name: Set up JDK 17
-      uses: actions/setup-java@v4
+      uses: actions/setup-java@c1e323688fd81a25caa38c78aa6df2d33d3e20d9 # v4.8.0
       with:
         java-version: 17
         distribution: 'temurin'
@@ -28,7 +28,7 @@ jobs:
       run: ./gradlew compileTestJava publishToMavenLocal check
 
     - name: Upload test results
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
       if: always()
       with:
         name: test-results
diff --git a/.github/workflows/publish-release-from-tag.yml b/.github/workflows/publish-release-from-tag.yml
index 466e2b63..d79c72ac 100644
--- a/.github/workflows/publish-release-from-tag.yml
+++ b/.github/workflows/publish-release-from-tag.yml
@@ -23,7 +23,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
         with:
           fetch-depth: 0
 
@@ -79,13 +79,13 @@ jobs:
           git checkout ${{ steps.determine-tag.outputs.tag }}
 
       - name: Set up JDK 17
-        uses: actions/setup-java@v4
+        uses: actions/setup-java@c1e323688fd81a25caa38c78aa6df2d33d3e20d9 # v4.8.0
         with:
           java-version: '17'
           distribution: 'temurin'
 
       - name: Setup Gradle
-        uses: gradle/gradle-build-action@v2
+        uses: gradle/gradle-build-action@a8f75513eafdebd8141bd1cd4e30fcd194af8dfa # v2.12.0
 
       - name: Run CI
         run: ./gradlew check