Release 2.5.3.

CHANGES.md

@@ -7,6 +7,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [2.5.3] 2022-04-27
+
+### Fixes
+
+- Fixed inflation vulnerability relating to ExitToNear and ExitToEthereum by [@birchmd], [@mfornet], and [@joshuajbouw]. Written by [@birchmd].
+
 ## [2.5.2] 2022-03-22
 
 ### Removed
@@ -238,7 +244,8 @@ struct SubmitResult {
 
 ## [1.0.0] - 2021-05-12
 
-[Unreleased]: https://github.com/aurora-is-near/aurora-engine/compare/2.5.2...develop
+[Unreleased]: https://github.com/aurora-is-near/aurora-engine/compare/2.5.3...develop
+[2.5.3]: https://github.com/aurora-is-near/aurora-engine/compare/2.5.2...2.5.3 
 [2.5.2]: https://github.com/aurora-is-near/aurora-engine/compare/2.5.1...2.5.2
 [2.5.1]: https://github.com/aurora-is-near/aurora-engine/compare/2.5.0...2.5.1
 [2.5.0]: https://github.com/aurora-is-near/aurora-engine/compare/2.4.0...2.5.0

README.md

@@ -14,9 +14,9 @@ documentation.
 
 Network | Contract ID         | Chain ID   | Version
 ------- | ------------------- | ---------- | ------
-Mainnet | [`aurora`][Mainnet] | 1313161554 | 2.4.0
-Testnet | [`aurora`][Testnet] | 1313161555 | 2.5.1
-Local   | `aurora.test.near`  | 1313161556 | 2.5.1
+Mainnet | [`aurora`][Mainnet] | 1313161554 | 2.5.3
+Testnet | [`aurora`][Testnet] | 1313161555 | 2.5.3
+Local   | `aurora.test.near`  | 1313161556 | 2.5.3
 
 [Mainnet]: https://explorer.near.org/accounts/aurora
 [Testnet]: https://explorer.testnet.near.org/accounts/aurora

VERSION

@@ -1 +1 @@
-2.5.2
+2.5.3

engine-precompiles/src/native.rs

@@ -269,6 +269,8 @@ impl Precompile for ExitToNear {
         // It's not allowed to call exit precompiles in static mode
         if is_static {
             return Err(ExitError::Other(Cow::from("ERR_INVALID_IN_STATIC")));
+        } else if context.address != Self::ADDRESS.raw() {
+            return Err(ExitError::Other(Cow::from("ERR_INVALID_IN_DELEGATE")));
         }
 
         // First byte of the input is a flag, selecting the behavior to be triggered:
@@ -473,6 +475,8 @@ impl Precompile for ExitToEthereum {
         // It's not allowed to call exit precompiles in static mode
         if is_static {
             return Err(ExitError::Other(Cow::from("ERR_INVALID_IN_STATIC")));
+        } else if context.address != Self::ADDRESS.raw() {
+            return Err(ExitError::Other(Cow::from("ERR_INVALID_IN_DELEGATE")));
         }
 
         // First byte of the input is a flag, selecting the behavior to be triggered:

engine-tests/src/tests/erc20_connector.rs

@@ -402,7 +402,7 @@ mod sim_tests {
         CallArgs, DeployErc20TokenArgs, FunctionCallArgsV2, SubmitResult,
     };
     use aurora_engine_types::types::Address;
-    use borsh::BorshSerialize;
+    use borsh::{BorshDeserialize, BorshSerialize};
     use near_sdk_sim::UserAccount;
     use serde_json::json;
 
@@ -414,6 +414,69 @@ mod sim_tests {
     const INITIAL_ETH_BALANCE: u64 = 777_777_777;
     const ETH_EXIT_AMOUNT: u64 = 111_111_111;
 
+    #[test]
+    fn test_ghsa_5c82_x4m4_hcj6_exploit() {
+        let TestExitToNearEthContext {
+            mut signer,
+            signer_address,
+            chain_id,
+            tester_address: _,
+            aurora,
+        } = test_exit_to_near_eth_common();
+
+        let constructor = test_utils::solidity::ContractConstructor::force_compile(
+            "src/tests/res",
+            "target/solidity_build",
+            "exploit.sol",
+            "Exploit",
+        );
+        let nonce = signer.use_nonce().into();
+        let deploy_tx = constructor.deploy_without_constructor(nonce);
+        let signed_tx = test_utils::sign_transaction(deploy_tx, Some(chain_id), &signer.secret_key);
+        let deploy_result = aurora.call("submit", &rlp::encode(&signed_tx));
+        let contract_address = match &deploy_result.status() {
+            near_sdk_sim::transaction::ExecutionStatus::SuccessValue(bytes) => {
+                let submit_result = SubmitResult::try_from_slice(bytes).unwrap();
+                Address::try_from_slice(test_utils::unwrap_success_slice(&submit_result)).unwrap()
+            }
+            _ => panic!("Unknown result: {:?}", deploy_result),
+        };
+        let contract = constructor.deployed_at(contract_address);
+
+        let nonce = signer.use_nonce().into();
+        let hacker_account = "hacker.near";
+        let hacker_account_bytes = hacker_account.as_bytes().to_vec();
+        let mut exploit_tx = contract.call_method_with_args(
+            "exploit",
+            &[ethabi::Token::Bytes(hacker_account_bytes)],
+            nonce,
+        );
+        exploit_tx.value = Wei::new_u64(ETH_EXIT_AMOUNT);
+        let signed_tx =
+            test_utils::sign_transaction(exploit_tx, Some(chain_id), &signer.secret_key);
+        aurora
+            .call("submit", &rlp::encode(&signed_tx))
+            .assert_success();
+
+        // check balances -- Hacker does not steal any funds!
+        assert_eq!(
+            nep_141_balance_of(
+                aurora.contract.account_id.as_str(),
+                &aurora.contract,
+                &aurora,
+            ),
+            INITIAL_ETH_BALANCE as u128
+        );
+        assert_eq!(
+            nep_141_balance_of(hacker_account, &aurora.contract, &aurora),
+            0
+        );
+        assert_eq!(
+            eth_balance_of(signer_address, &aurora),
+            Wei::new_u64(INITIAL_ETH_BALANCE)
+        );
+    }
+
     #[test]
     fn test_exit_to_near() {
         // Deploy Aurora; deploy NEP-141; bridge NEP-141 to ERC-20 on Aurora

engine-tests/src/tests/res/exploit.sol

@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-3.0
+
+pragma solidity ^0.8.6;
+
+contract Exploit {
+    address payable private owner;
+
+    constructor() {
+        owner = payable(msg.sender);
+    }
+
+    function exploit(bytes memory recipient) public payable {
+        require(msg.sender == owner);
+
+        bytes memory input = abi.encodePacked("\x00", recipient);
+        uint input_size = 1 + recipient.length;
+
+        assembly {
+            let res := delegatecall(gas(), 0xe9217bc70b7ed1f598ddd3199e80b093fa71124f, add(input, 32), input_size, 0, 32)
+        }
+
+        owner.transfer(msg.value);
+    }
+}
+