CVE-2023-30541: OpenZeppelin Contracts is a library for secure smart contract development. A function in the implementation contract may be inaccessible if its select...

Description

OpenZeppelin Contracts is a library for secure smart contract development. 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 and could cause a reduction in availability. The issue has been fixed in version 4.8.3. As a workaround 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.

Metrics

CVSS 3.1

5.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

EPSS Probability

0.81%

52.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Openzeppelin	Contracts	>= 3.2.0, < 4.8.3
Openzeppelin	Contracts Upgradeable	>= 3.2.0, < 4.8.3

References

Timeline

Published: Apr 17, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-30541?

OpenZeppelin Contracts is a library for secure smart contract development. 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 and could cause a reduction in availability. The issue has been fixed in version 4.8.3. As a workaround 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.

How severe is CVE-2023-30541?

CVE-2023-30541 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 0.81% probability of exploitation in the next 30 days.

How do I fix CVE-2023-30541?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.