How severe is CVE-2023-31146?

CVE-2023-31146 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-2023-31146 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-31146?

CVE-2023-31146 affects Vyperlang Vyper. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-31146?

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-2023-31146 published?

CVE-2023-31146 was published on 2023-05-11 and last updated on 2026-06-17.

CVE-2023-31146

CVE-2023-31146 is a high-severity vulnerability in Vyperlang Vyper 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-787.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Vyperlang Vyper
Published: 2023-05-11
Last modified: 2026-06-17

Description

Vyper is a Pythonic smart contract language for the Ethereum virtual machine. Prior to version 0.3.8, during codegen, the length word of a dynarray is written before the data, which can result in out-of-bounds array access in the case where the dynarray is on both the lhs and rhs of an assignment. The issue can cause data corruption across call frames. The expected behavior is to revert due to out-of-bounds array access. Version 0.3.8 contains a patch for this issue.

Frequently asked questions

What is CVE-2023-31146?: Vyper is a Pythonic smart contract language for the Ethereum virtual machine. Prior to version 0.3.8, during codegen, the length word of a dynarray is written before the data, which can result in out-of-bounds array access in the case where the dynarray is on both the lhs and rhs of an assignment. The issue can cause data corruption across call frames. The expected behavior is to revert due to out-of-bounds array access. Version 0.3.8 contains a patch for this issue.
How severe is CVE-2023-31146?: CVE-2023-31146 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-2023-31146 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-31146?: CVE-2023-31146 affects Vyperlang Vyper. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-31146?: 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-2023-31146 published?: CVE-2023-31146 was published on 2023-05-11 and last updated on 2026-06-17.

References

Affected products (1)

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

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