diff --git a/doc/82-Changelog.md b/doc/82-Changelog.md
index 9ad75bd4..7456053f 100644
--- a/doc/82-Changelog.md
+++ b/doc/82-Changelog.md
@@ -13,6 +13,7 @@ next (will be 1.9.0)
 
 ### Import and Sync
 * FIX: string property modifiers now preserve NULL values (#2371)
+* FIX: "to int" property modifiers now fails for non-string values (#2372)
 * FEATURE: introduce 'disable' as your purge action on Sync (#2285)
 * FEATURE: there is now a simple "group by" Property Modifier (#2317)
 
diff --git a/library/Director/PropertyModifier/PropertyModifierToInt.php b/library/Director/PropertyModifier/PropertyModifierToInt.php
index cfd3c23e..dca7db98 100644
--- a/library/Director/PropertyModifier/PropertyModifierToInt.php
+++ b/library/Director/PropertyModifier/PropertyModifierToInt.php
@@ -2,6 +2,7 @@
 
 namespace Icinga\Module\Director\PropertyModifier;
 
+use Icinga\Module\Director\Data\InvalidDataException;
 use Icinga\Module\Director\Hook\PropertyModifierHook;
 
 class PropertyModifierToInt extends PropertyModifierHook
@@ -24,5 +25,7 @@ class PropertyModifierToInt extends PropertyModifierHook
         if (is_string($value)) {
             return (int) $value;
         }
+
+        throw new InvalidDataException('String, integer or null', $value);
     }
 }