diff --git a/CHANGELOG.md b/CHANGELOG.md
index d36459c5..27758c3e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,8 @@ Note: In this file, do not use the hard wrap in the middle of a sentence for com
 
 ## [Unreleased]
 
+- Update `mdbook@latest` to 0.5.4.
+
 ## [2.82.10] - 2026-07-07
 
 - Update `tombi@latest` to 1.2.0.
diff --git a/manifests/mdbook.json b/manifests/mdbook.json
index aaed78a9..9bdd3edb 100644
--- a/manifests/mdbook.json
+++ b/manifests/mdbook.json
@@ -21,10 +21,10 @@
     }
   },
   "latest": {
-    "version": "0.5.3"
+    "version": "0.5.4"
   },
   "0.5": {
-    "version": "0.5.3"
+    "version": "0.5.4"
   },
   "0.5.4": {
     "x86_64_linux_musl": {