diff --git a/.github/workflows/book.yml b/.github/workflows/book.yml
index 5f20c520..66608029 100644
--- a/.github/workflows/book.yml
+++ b/.github/workflows/book.yml
@@ -14,7 +14,7 @@ jobs:
       - name: Setup mdBook
         uses: peaceiris/actions-mdbook@v1
         with:
-          mdbook-version: '0.4.4'
+          mdbook-version: '0.4.5'
 
       - name: Install mdbook-katex
         uses: actions-rs/cargo@v1
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f5411466..b27d1406 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -47,7 +47,7 @@ jobs:
       - name: Setup mdBook
         uses: peaceiris/actions-mdbook@v1
         with:
-          mdbook-version: '0.4.4'
+          mdbook-version: '0.4.5'
       - name: Test Orchard book
         run: mdbook test book/