CVE intelligence and bounded remediation

CVE-2023-31146 — Vyper is a Pythonic smart contract language for the Ethereum virtual machine

Critical CVSS 9.1

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.

Severity
Critical
CVSS
9.1 (3.1)
Published
2023-05-11
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-787

Affected products

  • vyperlang / vyper

Matched remediation archetype

Buffer bounds, memory safety, and memory corruption

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
  • Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
  • Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.

Remediate safely

  • Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
  • Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
  • Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.

Authoritative sources

Complete CVE record and remediation plan

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