diff --git a/src/decorator/string/IsIP.ts b/src/decorator/string/IsIP.ts
index 840f28afd1..fd3d160086 100644
--- a/src/decorator/string/IsIP.ts
+++ b/src/decorator/string/IsIP.ts
@@ -11,6 +11,7 @@ export const IS_IP = 'isIp';
  * If given value is not a string, then it returns false.
  */
 export function isIP(value: unknown, version?: IsIpVersion): boolean {
+  /* eslint-disable-next-line @typescript-eslint/no-unnecessary-type-assertion */
   const versionStr = version ? (`${version}` as '4' | '6') : undefined;
   return typeof value === 'string' && isIPValidator(value, versionStr);
 }
diff --git a/src/decorator/string/IsISBN.ts b/src/decorator/string/IsISBN.ts
index afd1a3bda6..f3116b93c7 100644
--- a/src/decorator/string/IsISBN.ts
+++ b/src/decorator/string/IsISBN.ts
@@ -11,6 +11,7 @@ export const IS_ISBN = 'isIsbn';
  * If given value is not a string, then it returns false.
  */
 export function isISBN(value: unknown, version?: IsISBNVersion): boolean {
+  /* eslint-disable-next-line @typescript-eslint/no-unnecessary-type-assertion */
   const versionStr = version ? (`${version}` as '10' | '13') : undefined;
   return typeof value === 'string' && isIsbnValidator(value, versionStr);
 }