diff --git a/src/security/validator.cpp b/src/security/validator.cpp
index 338ef9f..7f97926 100644
--- a/src/security/validator.cpp
+++ b/src/security/validator.cpp
@@ -142,7 +142,7 @@
           }
         }
     }
-  catch (const Signature::Error& e)
+  catch (Signature::Error& e)
     {
       return false;
     }
@@ -180,11 +180,11 @@
           }
         }
     }
-  catch (const Signature::Error& e)
+  catch (Signature::Error& e)
     {
       return false;
     }
-  catch (const Block::Error& e)
+  catch (Block::Error& e)
     {
       return false;
     }
@@ -209,7 +209,7 @@
           }
         }
     }
-  catch (const Signature::Error& e)
+  catch (Signature::Error& e)
     {
       return false;
     }
@@ -237,7 +237,7 @@
                                     sig.getValue().value(),
                                     sig.getValue().value_size());
     }
-  catch (const CryptoPP::Exception& e)
+  catch (CryptoPP::Exception& e)
     {
       return false;
     }
@@ -264,7 +264,7 @@
       else
         return false;
     }
-  catch (const CryptoPP::Exception& e)
+  catch (CryptoPP::Exception& e)
     {
       return false;
     }