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TI-2022-11796 Aliases CVE-2022-29255GHSA-4v9q-cgpw-cf38

Multiple evaluation of contract address in call in vyper

Priority HIGH 75CWE-670Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · High · Low
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. In versions prior to 0.3.4 when a calling an external contract with no return value, the contract address (including side effects) could be evaluated twice. This may result in incorrect outcomes for contracts. This issue has been addressed in v0.3.4.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.01349 71st percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed vyper (vyperlang): 0.3.4vyper (PyPI): 0.3.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
vyperlangvyperbefore 0.3.40.3.4Patch availableCNA
—vyper (PyPI)before 0.3.40.3.4Patch availableGHSA-4v9q-cgpw-cf38
  • vyper Vendorvyperlang Affected before 0.3.4 Fixed in 0.3.4 Patch available CNA
  • vyper (PyPI) Vendor— Affected before 0.3.4 Fixed in 0.3.4 Patch available GHSA-4v9q-cgpw-cf38

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:*:*:*before 0.3.4Vulnerablevyperlang
  • cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:*:*:* Versions before 0.3.4 Vulnerable ·vyperlang

Remediation

  • Fix · CNA vyper (vyperlang) Fixed in 0.3.4
  • Fix · GHSA-4v9q-cgpw-cf38 vyper (PyPI) Fixed in 0.3.4 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2022-29255
  2. 2026-10-03 Alias added: GHSA-4v9q-cgpw-cf38

References

Exploit 1

Patch 1

Advisory 1

Other 2

  • 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-2024-21531 vyper performs double eval of the argument of sqrt CVSS 3.1MEDIUM 5.3
  • TI-2024-21527 vyper performs incorrect topic logging in raw_log 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