diff --git a/.github/workflows/boj-build.yml b/.github/workflows/boj-build.yml
index 410dc3c..ddeab5d 100644
--- a/.github/workflows/boj-build.yml
+++ b/.github/workflows/boj-build.yml
@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - name: Trigger BoJ Server (Casket/ssg-mcp)
         run: |
           # Send a secure trigger to boj-server to build this repository
diff --git a/.github/workflows/casket-pages.yml b/.github/workflows/casket-pages.yml
index 587a8cd..1f8cdc7 100644
--- a/.github/workflows/casket-pages.yml
+++ b/.github/workflows/casket-pages.yml
@@ -35,7 +35,7 @@ jobs:
           cabal-version: '3.10'
 
       - name: Cache Cabal
-        uses: actions/cache@cdf6c1fa76f9f475f3d7449005a359c84ca0f306 # v4
+        uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v4
         with:
           path: |
             ~/.cabal/packages
diff --git a/.github/workflows/compilation_tests.yml b/.github/workflows/compilation_tests.yml
index 028bd05..e24d152 100644
--- a/.github/workflows/compilation_tests.yml
+++ b/.github/workflows/compilation_tests.yml
@@ -51,19 +51,19 @@ jobs:
           toolchain: ${{ matrix.rust }}
 
       - name: Cache cargo registry
-        uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4
+        uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v4
         with:
           path: ~/.cargo/registry
           key: ${{ runner.os }}-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Cache cargo index
-        uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4
+        uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v4
         with:
           path: ~/.cargo/git
           key: ${{ runner.os }}-cargo-index-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Cache cargo build
-        uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4
+        uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v4
         with:
           path: impl/rust-cli/target
           key: ${{ runner.os }}-cargo-build-${{ matrix.rust }}-${{ hashFiles('**/Cargo.lock') }}
diff --git a/.github/workflows/lean-verification.yml b/.github/workflows/lean-verification.yml
index 975ff78..9a89893 100644
--- a/.github/workflows/lean-verification.yml
+++ b/.github/workflows/lean-verification.yml
@@ -45,7 +45,7 @@ jobs:
           toolchain: stable
 
       - name: Cache Lean build
-        uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4
+        uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v4
         with:
           path: proofs/lean4/.lake
           key: ${{ runner.os }}-lean-${{ hashFiles('proofs/lean4/lakefile.lean', 'proofs/lean4/lean-toolchain') }}
diff --git a/.github/workflows/scorecard.yml b/.github/workflows/scorecard.yml
index 0088c99..8088d30 100644
--- a/.github/workflows/scorecard.yml
+++ b/.github/workflows/scorecard.yml
@@ -21,7 +21,7 @@ jobs:
           persist-credentials: false
       
       - name: Run Scorecard
-        uses: ossf/scorecard-action@62b2cac7ed8198b15735ed49ab1e5cf35480ba46 # v2.4.0
+        uses: ossf/scorecard-action@4eaacf0543bb3f2c246792bd56e8cdeffafb205a # v2.4.3
         with:
           results_file: results.sarif
           results_format: sarif
diff --git a/.github/workflows/validation.yml b/.github/workflows/validation.yml
index ca12995..bb6fedb 100644
--- a/.github/workflows/validation.yml
+++ b/.github/workflows/validation.yml
@@ -24,7 +24,7 @@ jobs:
           components: rustfmt, clippy
 
       - name: Cache Rust dependencies
-        uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4
+        uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v4
         with:
           path: |
             ~/.cargo/bin/