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TI-2023-24874 Aliases CVE-2023-46247GHSA-6m97-7527-mh74

Vyper has incorrect storage layout for contracts containing large arrays

Priority LOW 34CWE-193Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Contracts containing large arrays might underallocate the number of slots they need by 1. Prior to v0.3.8, the calculation to determine how many slots a storage variable needed used `math.ceil(type_.size_in_bytes / 32)`. The intermediate floating point step can produce a rounding error if there are enough bits set in the IEEE-754 mantissa. Roughly speaking, if `type_.size_in_bytes` is large (> 2**46), and slightly less than a power of 2, the calculation can overestimate how many slots are needed by 1. If `type_.size_in_bytes` is slightly more than a power of 2, the calculation can underestimate how many slots are needed by 1. This issue is patched in version 0.3.8.

Why it matters now

EPSS 0.00692 53rd percentileScored 2026-11-07
Fix Fixed vyper (vyperlang): 0.3.8vyper (PyPI): 0.3.8

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
vyperlangvyperbefore 0.3.80.3.8Patch availableCNA
—vyper (PyPI)before 0.3.80.3.8Patch availableGHSA-6m97-7527-mh74
  • vyper Vendorvyperlang Affected before 0.3.8 Fixed in 0.3.8 Patch available CNA
  • vyper (PyPI) Vendor— Affected before 0.3.8 Fixed in 0.3.8 Patch available GHSA-6m97-7527-mh74

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:python:*:*before 0.3.8Vulnerablevyperlang
  • cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:python:*:* Versions before 0.3.8 Vulnerable ·vyperlang

Remediation

  • Fix · CNA vyper (vyperlang) Fixed in 0.3.8
  • Fix · GHSA-6m97-7527-mh74 vyper (PyPI) Fixed in 0.3.8 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-46247
  2. 2026-10-03 Alias added: GHSA-6m97-7527-mh74

References

Patch 1

Advisory 2

Other 3

  • TI-2024-16182 Vyper bounds check on built-in `slice()` function can be overflowed CVSS 3.1CRITICAL 9.8
  • TI-2024-14992 concat built-in can corrupt memory in vyper CVSS 3.1CRITICAL 9.8
  • TI-2024-16184 Vyper array negative index vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2022-08657 Integer bounds error in Vyper CVSS 3.1CRITICAL 9.8
  • TI-2022-11796 Multiple evaluation of contract address in call in vyper CVSS 3.1HIGH 8.2
  • TI-2024-21531 vyper performs double eval of the argument of sqrt CVSS 3.1MEDIUM 5.3
See all 37 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences