diff --git a/dlls/rsaenh/rsaenh.c b/dlls/rsaenh/rsaenh.c
index 3a2d7126ca4..f854e35dfdf 100644
--- a/dlls/rsaenh/rsaenh.c
+++ b/dlls/rsaenh/rsaenh.c
@@ -3797,7 +3797,7 @@ BOOL WINAPI RSAENH_CPGetHashParam(HCRYPTPROV hProv, HCRYPTHASH hHash, DWORD dwPa
  *                     CRYPT_EXPORT, CRYPT_READ, CRYPT_WRITE, CRYPT_MAC
  *   - KP_IV: Initialization vector
  */
-BOOL WINAPI RSAENH_CPSetKeyParam(HCRYPTPROV hProv, HCRYPTKEY hKey, DWORD dwParam, BYTE *pbData, 
+BOOL WINAPI RSAENH_CPSetKeyParam(HCRYPTPROV hProv, HCRYPTKEY hKey, DWORD dwParam, BYTE *pbData,
                                  DWORD dwFlags)
 {
     CRYPTKEY *pCryptKey;
@@ -3815,13 +3815,19 @@ BOOL WINAPI RSAENH_CPSetKeyParam(HCRYPTPROV hProv, HCRYPTKEY hKey, DWORD dwParam
         SetLastError(NTE_BAD_FLAGS);
         return FALSE;
     }
-    
+
     if (!lookup_handle(&handle_table, hKey, RSAENH_MAGIC_KEY, (OBJECTHDR**)&pCryptKey))
     {
         SetLastError(NTE_BAD_KEY);
         return FALSE;
     }
-    
+
+    if (!pbData)
+    {
+        SetLastError(ERROR_INVALID_PARAMETER);
+        return FALSE;
+    }
+
     switch (dwParam) {
         case KP_PADDING:
             /* The MS providers only support PKCS5_PADDING */