diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6b8f989e..140d7148 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -27,7 +27,7 @@ jobs:
         tool:
           # Note: Specifying the version of valgrind and wasm-pack is not supported.
           - cargo-hack,cargo-llvm-cov,cargo-minimal-versions,parse-changelog,cross,nextest,shellcheck,shfmt,valgrind,wasm-pack,wasmtime,mdbook
-          - cargo-hack@0.5.12,cargo-llvm-cov@0.3.0,cargo-minimal-versions@0.1.3,parse-changelog@0.4.7,cross@0.2.1,nextest@0.9.11,shellcheck@0.8.0,shfmt@3.4.3,wasmtime@0.35.1,mdbook@0.4.17
+          - cargo-hack@0.5.12,cargo-llvm-cov@0.3.0,cargo-minimal-versions@0.1.3,parse-changelog@0.4.7,cross@0.2.1,nextest@0.9.11,shellcheck@0.8.0,shfmt@3.4.3,wasmtime@0.35.3,mdbook@0.4.18
           # Nextest supports basic version ranges as well
           - nextest@0.9
         include:
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 50e28391..c66f3f7e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,9 @@ Note: In this file, do not use the hard wrap in the middle of a sentence for com
 
 ## [Unreleased]
 
+- Update `mdbook@latest` to 0.4.18.
+- Update `wasmtime@latest` to 0.35.3.
+
 ## [1.3.1] - 2022-04-08
 
 - Update `cargo-llvm-cov@latest` to 0.3.0.
diff --git a/main.sh b/main.sh
index 81fc6ed2..b2beaad2 100755
--- a/main.sh
+++ b/main.sh
@@ -178,7 +178,7 @@ for tool in "${tools[@]}"; do
             ;;
         wasmtime)
             # https://github.com/bytecodealliance/wasmtime/releases
-            latest_version="0.35.1"
+            latest_version="0.35.3"
             repo="bytecodealliance/wasmtime"
             case "${OSTYPE}" in
                 linux*) target="x86_64-linux" ;;
@@ -196,7 +196,7 @@ for tool in "${tools[@]}"; do
             ;;
         mdbook)
             # https://github.com/rust-lang/mdBook/releases
-            latest_version="0.4.17"
+            latest_version="0.4.18"
             repo="rust-lang/mdBook"
             case "${OSTYPE}" in
                 linux*) target="x86_64-unknown-linux-gnu" ;;