diff --git a/.github/workflows/cargo-audit.yml b/.github/workflows/cargo-audit.yml
index 29d3ea4..d41307b 100644
--- a/.github/workflows/cargo-audit.yml
+++ b/.github/workflows/cargo-audit.yml
@@ -36,7 +36,7 @@ jobs:
       # changes are reviewed, not silently picked up from latest-stable).
       CARGO_AUDIT_VERSION: "0.22.1"
     steps:
-      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - uses: dtolnay/rust-toolchain@29eef336d9b2848a0b548edc03f92a220660cdb8 # stable
       - uses: Swatinem/rust-cache@e18b497796c12c097a38f9edb9d0641fb99eee32 # v2
       - name: Install cargo-audit
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e927464..41efb70 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 30
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
       - name: Install Rust toolchain (from rust-toolchain.toml)
         uses: dtolnay/rust-toolchain@29eef336d9b2848a0b548edc03f92a220660cdb8 # stable
@@ -48,7 +48,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 10
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - uses: EmbarkStudios/cargo-deny-action@6c8f9facfa5047ec02d8485b6bf52b587b7777d1 # v2
         with:
           command: check
diff --git a/.github/workflows/commitlint.yml b/.github/workflows/commitlint.yml
index 630cda2..4e21830 100644
--- a/.github/workflows/commitlint.yml
+++ b/.github/workflows/commitlint.yml
@@ -13,7 +13,7 @@ jobs:
     name: commitlint
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
         with:
           fetch-depth: 0
 
diff --git a/.github/workflows/dependency-review.yml b/.github/workflows/dependency-review.yml
index 5ce62ad..02d7ff4 100644
--- a/.github/workflows/dependency-review.yml
+++ b/.github/workflows/dependency-review.yml
@@ -22,7 +22,7 @@ jobs:
     name: Dependency review
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
       - uses: actions/dependency-review-action@2031cfc080254a8a887f58cffee85186f0e49e48 # v4
         with:
diff --git a/.github/workflows/gitleaks.yml b/.github/workflows/gitleaks.yml
index 779187b..6a78be4 100644
--- a/.github/workflows/gitleaks.yml
+++ b/.github/workflows/gitleaks.yml
@@ -29,7 +29,7 @@ jobs:
     name: gitleaks (secret scan)
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
         with:
           fetch-depth: 0  # full history so commit-range scan covers the whole tree
       - name: Install gitleaks
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 0ba98ad..0ab15e8 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -23,7 +23,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 30
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@4d04d5d9486b7bd6fa91e7baf45bbb4f8b9deedd # v4.0.0
diff --git a/.github/workflows/smoke.yml b/.github/workflows/smoke.yml
index 5a57f7f..41f3c2b 100644
--- a/.github/workflows/smoke.yml
+++ b/.github/workflows/smoke.yml
@@ -24,7 +24,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 20
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
       - name: Install Rust toolchain (from rust-toolchain.toml)
         uses: dtolnay/rust-toolchain@29eef336d9b2848a0b548edc03f92a220660cdb8 # stable