diff --git a/.github/workflows/concat-kdf.yml b/.github/workflows/concat-kdf.yml
index fbebf1d..b1c1006 100644
--- a/.github/workflows/concat-kdf.yml
+++ b/.github/workflows/concat-kdf.yml
@@ -28,7 +28,7 @@ jobs:
           - thumbv7em-none-eabi
           - wasm32-unknown-unknown
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@master
         with:
           toolchain: ${{ matrix.rust }}
@@ -43,7 +43,7 @@ jobs:
           - 1.56.0 # MSRV
           - stable
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@master
         with:
           toolchain: ${{ matrix.rust }}
diff --git a/.github/workflows/hkdf.yml b/.github/workflows/hkdf.yml
index 0f10c50..9c97bea 100644
--- a/.github/workflows/hkdf.yml
+++ b/.github/workflows/hkdf.yml
@@ -28,7 +28,7 @@ jobs:
           - thumbv7em-none-eabi
           - wasm32-unknown-unknown
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: RustCrypto/actions/cargo-cache@master
       - uses: dtolnay/rust-toolchain@master
         with:
@@ -49,7 +49,7 @@ jobs:
           - 1.41.0 # MSRV
           - stable
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: RustCrypto/actions/cargo-cache@master
       - uses: dtolnay/rust-toolchain@master
         with:
diff --git a/.github/workflows/workspace.yml b/.github/workflows/workspace.yml
index 2ac675c..a2c54c7 100644
--- a/.github/workflows/workspace.yml
+++ b/.github/workflows/workspace.yml
@@ -13,7 +13,7 @@ jobs:
   clippy:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: RustCrypto/actions/cargo-cache@master
       - uses: dtolnay/rust-toolchain@master
         with:
@@ -25,7 +25,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout sources
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Install stable toolchain
         uses: dtolnay/rust-toolchain@master