OpenZeppelin Contracts is a library for secure smart contract development. This issue concerns instances of Governor that use the module GovernorVotesQuorumFraction, a mechanism that determines quorum requirements as a percentage of the voting token's total supply. In affected instances, when a proposal is passed to lower the quorum requirements, past proposals may become executable if they had been defeated only due to lack of quorum, and the number of votes it received meets the new quorum requirement. Analysis of instances on chain found only one proposal that met this condition, and we are actively monitoring for new occurrences of this particular issue. This issue has been patched in v4.7.2. Users are advised to upgrade. Users unable to upgrade should consider avoiding lowering quorum requirements if a past proposal was defeated for lack of quorum.
OpenZeppelin Contracts is a library for secure smart contract development. Contracts using the cross chain utilities for Arbitrum L2, CrossChainEnabledArbitrumL2 or LibArbitrumL2, will classify direct interactions of externally owned accounts (EOAs) as cross chain calls, even though they are not started on L1. This issue has been patched in v4.7.2. Users are advised to upgrade. There are no known workarounds for this issue.
Impact
The target contract of an EIP-165 supportsInterface query can cause unbounded gas consumption by returning a lot of data, while it is generally assumed that this operation has a bounded cost.
Patches
The issue has been fixed in v4.7.2.
References
https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3587
For more information
If you have any questions or comments about this advisory, or need assistance deploying a fix, email us at security@openzeppelin.com.
OpenZeppelin Contracts is a library for secure smart contract development. Before version 4.4.1 but after 3.2.0, initializer functions that are invoked separate from contract creation (the most prominent example being minimal proxies) may be reentered if they make an untrusted non-view external call. Once an initializer has finished running it can never be re-executed. However, an exception put in place to support multiple inheritance made reentrancy possible in the scenario described above, breaking the expectation that there is a single execution. Note that upgradeable proxies are commonly initialized together with contract creation, where reentrancy is not feasible, so the impact of this issue is believed to be minor. This issue has been patched, please upgrade to version 4.4.1. As a workaround, avoid untrusted external calls during initialization.
OpenZeppelin Contracts is a library for secure smart contract development. The ERC721Consecutive contract designed for minting NFTs in batches does not update balances when a batch has size 1 and consists of a single token. Subsequent transfers from the receiver of that token may overflow the balance as reported by balanceOf. The issue exclusively presents with batches of size 1. The issue has been patched in 4.8.2.
OpenZeppelin Contracts is a library for secure smart contract development. The proposal creation entrypoint (propose) in GovernorCompatibilityBravo allows the creation of proposals with a signatures array shorter than the calldatas array. This causes the additional elements of the latter to be ignored, and if the proposal succeeds the corresponding actions would eventually execute without any calldata. The ProposalCreated event correctly represents what will eventually execute, but the proposal parameters as queried through getActions appear to respect the original intended calldata. This issue has been patched in 4.8.3. As a workaround, ensure that all proposals that pass through governance have equal length signatures and calldatas parameters.
Impact
A function in the implementation contract may be inaccessible if its selector clashes with one of the proxy's own selectors. Specifically, if the clashing function has a different signature with incompatible ABI encoding, the proxy could revert while attempting to decode the arguments from calldata.
The probability of an accidental clash is negligible, but one could be caused deliberately.
Patches
The issue has been fixed in v4.8.3.
Workarounds
If a function appears to be inaccessible for this reason, it may be possible to craft the calldata such that ABI decoding does not fail at the proxy and the function is properly proxied through.
References
https://github.com/OpenZeppelin/openzeppelin-contracts/pull/4154
Impact
OpenZeppelin Contracts is a library for secure smart contract development. Starting in version 4.0.0 and prior to version 4.9.3, contracts using ERC2771Context along with a custom trusted forwarder may see msgSender return address(0) in calls that originate from the forwarder with calldata shorter than 20 bytes. This combination of circumstances does not appear to be common, in particular it is not the case for MinimalForwarder from OpenZeppelin Contracts, or any deployed forwarder the team is aware of, given that the signer address is appended to all calls that originate from these forwarders.
Patches
The problem has been patched in v4.9.3.
Context Merge conflict resolution issue when porting the v5.0.1 Multicall update to the v4.9 branch caused a duplicated line.
Impact Versions using Multicall from @openzeppelin/contracts@4.9.4 and @openzeppelin/contracts-upgradeable@4.9.4 will execute each subcall twice. Concretely, this exposes a user to unintentionally duplicate operations like asset transfers.
Patches The duplicated delegatecall was removed in 4.9.5. The 4.9.4 version is marked as deprecated.