diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 98b8300..27449a1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -50,7 +50,7 @@ jobs:
         components: rustfmt, clippy
 
     - name: Cache cargo registry
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: |
           ~/.cargo/registry
@@ -114,7 +114,7 @@ jobs:
         toolchain: stable
 
     - name: Cache cargo registry
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: |
           ~/.cargo/registry
@@ -152,7 +152,7 @@ jobs:
         toolchain: stable
 
     - name: Cache cargo registry
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: |
           ~/.cargo/registry
@@ -187,7 +187,7 @@ jobs:
         toolchain: stable
 
     - name: Cache cargo registry
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: |
           ~/.cargo/registry
@@ -225,7 +225,7 @@ jobs:
         toolchain: 1.85  # Full support for edition 2024
 
     - name: Cache cargo registry
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: |
           ~/.cargo/registry
@@ -260,7 +260,7 @@ jobs:
         components: llvm-tools-preview
 
     - name: Cache cargo registry
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: |
           ~/.cargo/registry
diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index eb00cf0..ada6034 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -35,7 +35,7 @@ jobs:
         toolchain: 1.85.0
 
     - name: Cache cargo registry
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: |
           ~/.cargo/registry
diff --git a/.github/workflows/formal-verification.yml b/.github/workflows/formal-verification.yml
index a9a1bdc..601bec9 100644
--- a/.github/workflows/formal-verification.yml
+++ b/.github/workflows/formal-verification.yml
@@ -30,19 +30,19 @@ jobs:
         toolchain: stable
     
     - name: Cache cargo registry
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: ~/.cargo/registry
         key: ${{ runner.os }}-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
     
     - name: Cache cargo index
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: ~/.cargo/git
         key: ${{ runner.os }}-cargo-index-${{ hashFiles('**/Cargo.lock') }}
     
     - name: Cache cargo build
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: target
         key: ${{ runner.os }}-cargo-build-target-${{ hashFiles('**/Cargo.lock') }}
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 522c687..7bb359e 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -33,7 +33,7 @@ jobs:
         toolchain: stable
 
     - name: Cache cargo registry
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: |
           ~/.cargo/registry
@@ -66,7 +66,7 @@ jobs:
         toolchain: stable
 
     - name: Cache cargo registry
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: |
           ~/.cargo/registry
@@ -97,7 +97,7 @@ jobs:
         toolchain: stable
 
     - name: Cache cargo registry
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: |
           ~/.cargo/registry