CVE-2023-42441: Vyper has incorrect re-entrancy lock when key is empty string
Impact
Locks of the type @nonreentrant("") or @nonreentrant('') do not produce reentrancy checks at runtime.
Vyper @nonreentrant("") # unprotected @external def bar(): pass
@nonreentrant("lock") # protected @external def foo(): pass Patches
Patched in #3605
Workarounds
The lock name should be a non-empty string.
References Are there any links users can visit to find out more?
Other sources
Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Starting in version 0.2.9 and prior to version 0.3.10, locks of the type @nonreentrant("") or @nonreentrant('') do not produce reentrancy checks at runtime. This issue is fixed in version 0.3.10. As a workaround, ensure the lock name is a non-empty string.
— MITRE
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is CVE-2023-42441?
CVE-2023-42441 is a vulnerability in the Vyper smart contract language that allows reentrancy attacks.
What is the impact of CVE-2023-42441?
The impact of CVE-2023-42441 is that locks with the `@nonreentrant` decorator do not produce reentrancy checks at runtime, making the smart contract vulnerable to reentrancy attacks.
How do I fix CVE-2023-42441?
To fix CVE-2023-42441, update to Vyper version 0.3.10 or higher.
Where can I find more information about CVE-2023-42441?
You can find more information about CVE-2023-42441 at the following references: [Link 1](https://github.com/vyperlang/vyper/commit/0b740280c1e3c5528a20d47b29831948ddcc6d83), [Link 2](https://github.com/vyperlang/vyper/pull/3605), [Link 3](https://github.com/vyperlang/vyper/security/advisories/GHSA-3hg2-r75x-g69m).
What is the severity of CVE-2023-42441?
CVE-2023-42441 has a severity rating of 5.3 (medium).