Parity Technologies Frontier

Frontier is Substrate's Ethereum compatibility layer. A security issue was discovered affecting parsing of the RPC result of the exit reason in case of EVM reversion. In release build, this would cause the exit reason being incorrectly parsed and returned by RPC. In debug build, this would cause an overflow panic. No action is needed unless you have a bridge node that needs to distinguish different reversion exit reasons and you used RPC for this. There are currently no known workarounds.

Published: 2022-08-19T20:25:10.000Z
Updated: 2025-04-23T17:48:19.789Z

Frontier is Substrate's Ethereum compatibility layer. In affected versions the truncation done when converting between EVM balance type and Substrate balance type was incorrectly implemented. This leads to possible discrepancy between appeared EVM transfer value and actual Substrate value transferred. It is recommended that an emergency upgrade to be planned and EVM execution temporarily paused in the mean time. The issue is patched in Frontier master branch commit fed5e0a9577c10bea021721e8c2c5c378e16bf66 and polkadot-v0.9.22 branch commit e3e427fa2e5d1200a784679f8015d4774cedc934. This vulnerability affects only EVM internal states, but not Substrate balance states or node. You can temporarily pause EVM execution (by setting up a Substrate `CallFilter` that disables `pallet-evm` and `pallet-ethereum` calls before the patch can be applied.

Published: 2022-07-06T17:15:14.000Z
Updated: 2025-04-23T18:04:45.882Z