diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Revision history for pms-domain-model
 
+## 0.1.1.0 -- 2025-09-15
+
+* Fixed validateMessage.
+
 ## 0.1.0.0 -- 2025-09-07
 
 * Support invalidChars configs.
diff --git a/pms-domain-model.cabal b/pms-domain-model.cabal
--- a/pms-domain-model.cabal
+++ b/pms-domain-model.cabal
@@ -20,7 +20,7 @@
 -- PVP summary:     +-+------- breaking API changes
 --                  | | +----- non-breaking API additions
 --                  | | | +--- code changes with no API change
-version:            0.1.0.0
+version:            0.1.1.0
 
 -- A short (one-line) description of the package.
 synopsis:           pms-domain-model
diff --git a/src/PMS/Domain/Model/DS/Utility.hs b/src/PMS/Domain/Model/DS/Utility.hs
--- a/src/PMS/Domain/Model/DS/Utility.hs
+++ b/src/PMS/Domain/Model/DS/Utility.hs
@@ -95,12 +95,20 @@
 -- |
 --
 validateMessage :: [String] ->  [String] -> String -> IO String
-validateMessage invalidChars invalidCmds cmd = case words cmd of
-  [] -> return cmd
-  (c : args) -> do
-    _ <- validateCommand invalidChars invalidCmds c
-    _ <- validateArgs invalidChars args
-    return cmd
+validateMessage invalidChars invalidCmds cmd = do
+  let tcmd = T.pack cmd
+
+  mapM_ (\seqStr ->
+          when (T.pack seqStr `T.isInfixOf` tcmd) $
+            E.throwString $ "Command contains forbidden sequence: " ++ seqStr
+        ) invalidChars
+
+  mapM_ (\seqStr ->
+          when (T.pack seqStr `T.isInfixOf` tcmd) $
+            E.throwString $ "Command contains forbidden sequence: " ++ seqStr
+        ) invalidCmds
+
+  return cmd
 
 -- |
 --