openzeppelin-confidential-contracts vulnerability

OpenZeppelin Confidential Contracts is an experimental library for developing applications on the Zama fhEVM. Prior to 0.3.1, the ERC7984 contract tracked confidential total supply with an euint64 value, and an overflowing internal _mint operation could fail silently. The wrap and onTransferReceived functions in contracts/token/ERC7984/extensions/ERC7984ERC20Wrapper.sol did not handle that failure, so a user could transfer the underlying token without receiving the corresponding confidential wrapped token. With the default rate(), the wrapper fills after approximately 18.4 trillion tokens, and subsequent wrapping requests can cause loss of funds. This issue is fixed in version 0.3.1.

Published 13 Aug 2026Updated 18 Sep 20264 sources
CVSS 6.6

What happened

OpenZeppelin Confidential Contracts is an experimental library for developing applications on the Zama fhEVM. Prior to 0.3.1, the ERC7984 contract tracked confidential total supply with an euint64 value, and an overflowing internal _mint operation could fail silently. The wrap and onTransferReceived functions in contracts/token/ERC7984/extensions/ERC7984ERC20Wrapper.sol did not handle that failure, so a user could transfer the underlying token without receiving the corresponding confidential wrapped token. With the default rate(), the wrapper fills after approximately 18.4 trillion tokens, and subsequent wrapping requests can cause loss of funds. This issue is fixed in version 0.3.1.

Affected versions

openzeppelin-confidential-contracts: < 0.3.1 Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

No public PoC reference has passed the current publication threshold.