How severe is CVE-2023-42441?

CVE-2023-42441 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2023-42441 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-42441?

CVE-2023-42441 affects Vyperlang Vyper. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-42441?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-42441 published?

CVE-2023-42441 was published on 2023-09-18 and last updated on 2026-06-17.

CVE-2023-42441

CVE-2023-42441 is a medium-severity vulnerability in Vyperlang Vyper with a CVSS 3.x base score of 5.3. 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-667.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (34th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-667
Affected product: Vyperlang Vyper
Published: 2023-09-18
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2023-42441?: 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.
How severe is CVE-2023-42441?: CVE-2023-42441 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2023-42441 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-42441?: CVE-2023-42441 affects Vyperlang Vyper. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-42441?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-42441 published?: CVE-2023-42441 was published on 2023-09-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:python:*:*

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