CVE-2021-41264
UUPSUpgradeable vulnerability in @openzeppelin/contracts
Description
### Impact Upgradeable contracts using `UUPSUpgradeable` may be vulnerable to an attack affecting uninitialized implementation contracts. We will update this advisory with more information soon. ### Patches A fix is included in version 4.3.2 of `@openzeppelin/contracts` and `@openzeppelin/contracts-upgradeable`. ### Workarounds 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). ### References [Post-mortem](https://forum.openzeppelin.com/t/uupsupgradeable-vulnerability-post-mortem/15680). ### For more information If you have any questions or comments about this advisory, or need assistance executing the mitigation, email us at security@openzeppelin.com.
How to fix CVE-2021-41264
To remediate CVE-2021-41264, upgrade the affected package to a fixed version below.
- —upgrade to 4.3.2 or later
- —upgrade to 4.3.2 or later
Is CVE-2021-41264 being exploited?
Low — EPSS is 0.6%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- >= 4.1.0, < 4.3.2
- >= 4.1.0, < 4.3.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | CRITICAL9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |