2 files changed, 6 insertions, 0 deletions
diff --git a/packages/contracts/src/2.0.0/protocol/AssetProxy/ERC20Proxy.sol b/packages/contracts/src/2.0.0/protocol/AssetProxy/ERC20Proxy.sol
index b5cec6b64..004c3892d 100644
--- a/packages/contracts/src/2.0.0/protocol/AssetProxy/ERC20Proxy.sol
+++ b/packages/contracts/src/2.0.0/protocol/AssetProxy/ERC20Proxy.sol
@@ -118,6 +118,9 @@ contract ERC20Proxy is
                 mstore(96, 0)
                 revert(0, 100)
             }
+
+            // Revert if undefined function is called
+            revert(0, 0)
         }
     }
 
diff --git a/packages/contracts/src/2.0.0/protocol/AssetProxy/ERC721Proxy.sol b/packages/contracts/src/2.0.0/protocol/AssetProxy/ERC721Proxy.sol
index 6a70c9f60..9d0bc0f74 100644
--- a/packages/contracts/src/2.0.0/protocol/AssetProxy/ERC721Proxy.sol
+++ b/packages/contracts/src/2.0.0/protocol/AssetProxy/ERC721Proxy.sol
@@ -152,6 +152,9 @@ contract ERC721Proxy is
                 mstore(96, 0)
                 revert(0, 100)
             }
+
+            // Revert if undefined function is called
+            revert(0, 0)
         }
     }