fix(crosschain): add emptiness check for topic array in event parsi…

…ng (#1556)

* add check for topic len

* changelogs

changelog.md

@@ -38,6 +38,7 @@
 * [1525](https://github.com/zeta-chain/node/pull/1525) - relax EVM chain block header length check 1024->4096
 * [1522](https://github.com/zeta-chain/node/pull/1522/files) - block `distribution` module account from receiving zeta
 * [1528](https://github.com/zeta-chain/node/pull/1528) - fix panic caused on decoding malformed BTC addresses
+* [1556](https://github.com/zeta-chain/node/pull/1556) - add emptiness check for topic array in event parsing
 * [1555](https://github.com/zeta-chain/node/pull/1555) - Reduce websocket message limit to 10MB
 
 ### Refactoring

x/crosschain/keeper/evm_hooks.go

@@ -275,6 +275,9 @@ func (k Keeper) ParseZRC20WithdrawalEvent(ctx sdk.Context, log ethtypes.Log) (*z
 	if err != nil {
 		return nil, err
 	}
+	if len(log.Topics) == 0 {
+		return nil, fmt.Errorf("ParseZRC20WithdrawalEvent: invalid log - no topics")
+	}
 	event, err := zrc20ZEVM.ParseWithdrawal(log)
 	if err != nil {
 		return nil, err
@@ -306,6 +309,9 @@ func ParseZetaSentEvent(log ethtypes.Log, connectorZEVM ethcommon.Address) (*con
 	if err != nil {
 		return nil, err
 	}
+	if len(log.Topics) == 0 {
+		return nil, fmt.Errorf("ParseZetaSentEvent: invalid log - no topics")
+	}
 	event, err := zetaConnectorZEVM.ParseZetaSent(log)
 	if err != nil {
 		return nil, err