diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index ae3e64d..84eb826 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -11,16 +11,16 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3
 
       - name: Set up Java 17
-        uses: actions/setup-java@v3
+        uses: actions/setup-java@17f84c3641ba7b8f6deff6309fc4c864478f5d62 # v3
         with:
           distribution: 'zulu'
           java-version: '17'
 
       - name: Cache Gradle Dependencies
-        uses: actions/cache@v3
+        uses: actions/cache@6f8efc29b200d32929f49075959781ed54ec270c # v3
         with:
           path: |
             ~/.gradle/caches
diff --git a/.github/workflows/jira-issue-create.yml b/.github/workflows/jira-issue-create.yml
index 103e302..db3e6df 100644
--- a/.github/workflows/jira-issue-create.yml
+++ b/.github/workflows/jira-issue-create.yml
@@ -12,7 +12,7 @@ jobs:
     name: SDK Bot Jira Issue Creation
     steps:
       - name: Login
-        uses: atlassian/gajira-login@master
+        uses: atlassian/gajira-login@ca13f8850ea309cf44a6e4e0c49d9aa48ac3ca4c # v3
         env:
           JIRA_BASE_URL: ${{ secrets.JIRA_BASE_URL }}
           JIRA_USER_EMAIL: ${{ secrets.JIRA_USER_EMAIL }}
@@ -20,7 +20,7 @@ jobs:
 
       - name: Create issue
         id: create
-        uses: atlassian/gajira-create@master
+        uses: atlassian/gajira-create@1ff0b6bd115a780592b47bfbb63fc4629132e6ec # v3
         with:
           project: ${{ secrets.JIRA_PROJECT }}
           issuetype: Task
diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 6d75335..24d6f71 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -11,10 +11,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3
 
       - name: Set up Java 17
-        uses: actions/setup-java@v3
+        uses: actions/setup-java@17f84c3641ba7b8f6deff6309fc4c864478f5d62 # v3
         with:
           distribution: 'zulu'
           java-version: '11'
diff --git a/.github/workflows/perf-test.yml b/.github/workflows/perf-test.yml
index bc10675..1aee585 100644
--- a/.github/workflows/perf-test.yml
+++ b/.github/workflows/perf-test.yml
@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
         with:
           fetch-depth: 0
 
@@ -31,7 +31,7 @@ jobs:
 
       - name: Generate GitHub App token
         id: generate-token
-        uses: peter-murray/workflow-application-token-action@v2
+        uses: peter-murray/workflow-application-token-action@8e1ba3bf1619726336414f1014e37f17fbadf1db # v2
         with:
           application_id: ${{ secrets.EVALUATION_PROXY_INTEGRATION_APP_ID }}
           application_private_key: ${{ secrets.EVALUATION_PROXY_INTEGRATION_KEY }}
diff --git a/.github/workflows/release.yaml b/.github/workflows/release.yaml
index 0963e47..942ddd9 100644
--- a/.github/workflows/release.yaml
+++ b/.github/workflows/release.yaml
@@ -17,10 +17,10 @@ jobs:
       # SETUP & VALIDATION
 
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3
 
       - name: Set up Java 17
-        uses: actions/setup-java@v3
+        uses: actions/setup-java@17f84c3641ba7b8f6deff6309fc4c864478f5d62 # v3
         with:
           distribution: 'zulu'
           java-version: '17'
@@ -28,7 +28,7 @@ jobs:
 
       - name: Validate Release Version
         if: ${{ startsWith(github.event.inputs.version, 'v') }}
-        uses: actions/github-script@v3
+        uses: actions/github-script@ffc2c79a5b2490bd33e0a41c1de74b877714d736 # v3
         with:
           script: |
             core.setFailed('Version ${{ github.event.inputs.version }} must not start with \'v\'. Use a non-prefixed semantic version, e.g. 1.2.3')
@@ -48,14 +48,14 @@ jobs:
       # SET VERSIONS
 
       - name: Set Version (Gradle)
-        uses: jacobtomlinson/gha-find-replace@v2
+        uses: jacobtomlinson/gha-find-replace@f485fdc3f67a6d87ae6e3d11e41f648c26d7aee3 # v2
         with:
           find: 'version = ".*"'
           replace: 'version = "${{ github.event.inputs.version }}"'
           include: 'core/build.gradle.kts'
           regex: true
       - name: Set Version (Const)
-        uses: jacobtomlinson/gha-find-replace@v2
+        uses: jacobtomlinson/gha-find-replace@f485fdc3f67a6d87ae6e3d11e41f648c26d7aee3 # v2
         with:
           find: 'const val EVALUATION_PROXY_VERSION = ".*"'
           replace: 'const val EVALUATION_PROXY_VERSION = "${{ github.event.inputs.version }}"'
@@ -77,7 +77,7 @@ jobs:
       # RELEASE DOCKER IMAGE
 
       - name: Login to DockerHub
-        uses: docker/login-action@v2
+        uses: docker/login-action@465a07811f14bebb1938fbed4728c6a1ff8901fc # v2
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
@@ -88,13 +88,13 @@ jobs:
 
       - name: Docker Metadata
         id: meta
-        uses: docker/metadata-action@v4
+        uses: docker/metadata-action@818d4b7b91585d195f67373fd9cb0332e31a7175 # v4
         with:
           tags: type=semver,pattern={{version}},value=v${{ github.event.inputs.version }}
           images: ${{ secrets.DOCKERHUB_USERNAME }}/evaluation-proxy
 
       - name: Docker Build and Push
-        uses: docker/build-push-action@v3
+        uses: docker/build-push-action@1104d471370f9806843c095c1db02b5a90c5f8b6 # v3
         with:
           context: .
           push: true
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 70b3ce1..4fde128 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -11,16 +11,16 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3
 
       - name: Set up Java 17
-        uses: actions/setup-java@v3
+        uses: actions/setup-java@17f84c3641ba7b8f6deff6309fc4c864478f5d62 # v3
         with:
           distribution: 'zulu'
           java-version: '17'
 
       - name: Cache Gradle Dependencies
-        uses: actions/cache@v3
+        uses: actions/cache@6f8efc29b200d32929f49075959781ed54ec270c # v3
         with:
           path: |
             ~/.gradle/caches