Critical

Vyper has incorrectly allocated named re-entrancy locks

  • Disclosed: 07.08.2023
  • Updated: 11.10.2026 15:17

Impact

In versions 0.2.15, 0.2.16 and 0.3.0, named re-entrancy locks are allocated incorrectly. Each function using a named re-entrancy lock gets a unique lock regardless of the key, allowing cross-function re-entrancy in contracts compiled with the susceptible versions. A specific set of conditions is required to result in misbehavior of affected contracts, specifically:

  • A .vy contract compiled with either of the following vyper versions: 0.2.15, 0.2.16, 0.3.0
  • A primary function that utilizes the @nonreentrant decorator with a specific key and does not strictly follow the check-effects-interaction pattern (i.e. contains an external call to an untrusted party before storage updates)
  • A secondary function that utilizes the same key and would be affected by the improper state caused by the primary function

Patches

https://github.com/vyperlang/vyper/pull/2439, https://github.com/vyperlang/vyper/pull/2514

Workarounds

Upgrade to 0.3.1 or higher

References

Technical post-mortem report: https://hackmd.io/@vyperlang/HJUgNMhs2

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Python (PyPI) vyper >= 0.2.15, < 0.3.1 0.3.1

References

CVSS score 8.7/10
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:H
Weakness (CWE)
CWE-863
Platform
Python (PyPI)
Package
vyper
Disclosed
07.08.2023
Updated
11.10.2026 15:17

Sources and licenses

OSV / GitHub Advisory Database - PYSEC-2023-142 - PyPA Advisory Database; CC BY 4.0

OSV / GitHub Advisory Database - GHSA-5824-cm3x-3c38 - CC BY 4.0

Vulnerability history: vyper

All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (47) in the archive
Total entries
47
First → latest
03.2020 10.2026
Without a fix
5
Exploited in attacks
0

Severity breakdown

  • Critical 3
  • High 14
  • Medium 20
  • Low 10

Disclosures per year

  1. 2020: 1
  2. 2021: 5
  3. 2022: 4
  4. 2023: 14
  5. 2024: 14
  6. 2025: 6
  7. 2026: 3
Severity:
  1. Critical · 9.8 CVE-2024-24563 < 0.4.0 0.4.0
  2. Critical · 9.8 CVE-2024-24561 < 0.4.0 0.4.0
  3. High · 7.3 CVE-2024-22419 >= 0.3.0, < 0.4.0 0.4.0
  4. High · 7.5 CVE-2023-46247 < 0.3.8 0.3.8
  5. High · 8.1 CVE-2023-42443 >= 0.3.4, < 0.3.10 0.3.10
  6. Vyper has incorrectly allocated named re-entrancy locks this entry
    Critical · 8.7 CVE-2023-39363 >= 0.2.15, < 0.3.1 0.3.1
  7. High · 7.5 CVE-2023-32058 < 0.3.8 0.3.8
  8. High · 7.5 CVE-2023-30837 < 0.3.8 0.3.8
  9. High · 7.5 CVE-2023-30629 >= 0.3.1, < 0.3.8 0.3.8
  10. High · 7.5 CVE-2022-29255 < 0.3.4 0.3.4
  11. High · 7.1 CVE-2022-24788 < 0.3.2 0.3.2
  12. High · 7.5 CVE-2022-24787 < 0.3.2 0.3.2
  13. High ghsa-7f92-rr6w-cq64 >= 0.2.13, < 0.2.15 0.2.15

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