How severe is CVE-2021-46320?

CVE-2021-46320 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2021-46320 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-46320?

CVE-2021-46320 affects Openzeppelin. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-46320?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-46320 published?

CVE-2021-46320 was published on 2022-02-04 and last updated on 2026-06-17.

CVE-2021-46320

Q: What is CVE-2021-46320?

In OpenZeppelin <=v4.4.0, initializer functions that are invoked separate from contract creation (the most prominent example being minimal proxies) may be reentered if they make an untrusted non-view external call. Once an initializer has finished running it can never be re-executed. However, an exception put in place to support multiple inheritance made reentrancy possible, breaking the expectation that there is a single execution.

CVE-2021-46320 is a high-severity vulnerability in Openzeppelin with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-665.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-665
Affected product: Openzeppelin
Published: 2022-02-04
Last modified: 2026-06-17

Description

In OpenZeppelin <=v4.4.0, initializer functions that are invoked separate from contract creation (the most prominent example being minimal proxies) may be reentered if they make an untrusted non-view external call. Once an initializer has finished running it can never be re-executed. However, an exception put in place to support multiple inheritance made reentrancy possible, breaking the expectation that there is a single execution.

Frequently asked questions

What is CVE-2021-46320?: In OpenZeppelin <=v4.4.0, initializer functions that are invoked separate from contract creation (the most prominent example being minimal proxies) may be reentered if they make an untrusted non-view external call. Once an initializer has finished running it can never be re-executed. However, an exception put in place to support multiple inheritance made reentrancy possible, breaking the expectation that there is a single execution.
How severe is CVE-2021-46320?: CVE-2021-46320 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2021-46320 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-46320?: CVE-2021-46320 affects Openzeppelin. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-46320?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-46320 published?: CVE-2021-46320 was published on 2022-02-04 and last updated on 2026-06-17.

References

https://github.com/OpenZeppelin/openzeppelin-contracts/security/advisories/GHSA-9c22-pwxw-p6hx

Affected products (1)

cpe:2.3:a:openzeppelin:openzeppelin:*:*:*:*:*:*:*:*

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