CVE-2021-41264

UUPSUpgradeable vulnerability in OpenZeppelin Contracts

Description

OpenZeppelin Contracts is a library for smart contract development. In affected versions upgradeable contracts using `UUPSUpgradeable` may be vulnerable to an attack affecting uninitialized implementation contracts. A fix is included in version 4.3.2 of `@openzeppelin/contracts` and `@openzeppelin/contracts-upgradeable`. For users unable to upgrade; initialize implementation contracts using `UUPSUpgradeable` by invoking the initializer function (usually called `initialize`). An example is provided [in the forum](https://forum.openzeppelin.com/t/security-advisory-initialize-uups-implementation-contracts/15301).

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.64%
Vendor Advisory openzeppelin.com
Affected: OpenZeppelin openzeppelin-contracts
Published at:
Updated at:

References

Link Tags
https://github.com/OpenZeppelin/openzeppelin-contracts/security/advisories/GHSA-5vp3-v4hc-gx76 third party advisory
https://github.com/OpenZeppelin/openzeppelin-contracts/commit/024cc50df478d2e8f78539819749e94d6df60592 third party advisory patch
https://forum.openzeppelin.com/t/security-advisory-initialize-uups-implementation-contracts/15301 patch vendor advisory mitigation issue tracking

Frequently Asked Questions

What is the severity of CVE-2021-41264?
CVE-2021-41264 has been scored as a critical severity vulnerability.
How to fix CVE-2021-41264?
To fix CVE-2021-41264, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-41264 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-41264 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-41264?
CVE-2021-41264 affects OpenZeppelin openzeppelin-contracts.
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