diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6ee14282..103b51cf 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -4,6 +4,7 @@ on: [push, pull_request]
 
 env:
   CARGO_TERM_COLOR: always
+  MSRV: "1.56"
 
 jobs:
   test:
@@ -29,5 +30,27 @@ jobs:
           toolchain: ${{ matrix.toolchain }}
 
       - name: Run Tests
-        run: ./scripts/test.sh
+        run: "cargo update && ./scripts/test.sh"
         shell: bash
+
+  msrv:
+    name: "Check MSRV"
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout Sources
+        uses: actions/checkout@v4
+
+      - name: Install Rust Nightly
+        uses: dtolnay/rust-toolchain@nightly
+
+      - name: Downgrade Dependencies to Minimal Versions
+        run: cargo update -Z minimal-versions
+
+      - name: Install MSRV
+        uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ env.MSRV }}
+
+      - name: Run Tests
+        run: ./scripts/test.sh
diff --git a/Cargo.toml b/Cargo.toml
index ad31f1f8..ac6cc475 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -28,7 +28,7 @@ percent-encoding = { version = "2.0", optional = true }
 aes-gcm = { version = "0.10.0", optional = true }
 hmac = { version = "0.12.0", optional = true }
 sha2 = { version = "0.10.0", optional = true }
-base64 = { version = "0.21", optional = true }
+base64 = { version = "0.21.4", optional = true }
 rand = { version = "0.8", optional = true }
 hkdf = { version = "0.12.0", optional = true }
 subtle = { version = "2.3", optional = true }