All vulnerabilities
GHSA-4v7v-gqf9-ww2g

Vyper: Call stack corruption when passing complex type containing non-base type members as argument

vyperpipLibraries & packages
Open in ThreatlineRecord JSON
CVSS
6.9Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)No scoreNo FIRST EPSS score in this snapshot yet
Fixed in0.2.6Fixed versionGitHub
Published6 Oct 2026Updated 6 Oct 2026GitHub

What fixes it

  • 0.2.6vyper, pipGitHub
  • 0.2.6vyper, PyPIOSVpip install "vyper>=0.2.6"

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

Impact

When we pass a multi-dimensional array (like [[1, 2], [3, 4]]) as an argument to internal/external functions we get incorrect output. This is due to a stack management issue, because it was assumed that the size of each subtype of an array/struct is 32, which is not always correct.

Example code:

@internal
def test_input(arr: int128[2][1], i: int128) -> (int128[2][1], int128):
    return arr, i

@external
def test_values(arr: int128[2][1], i: int128) -> (int128[2][1], int128):
    return self.test_input(arr, i)

Please see #2183 for further information

Patches

This problem was fixed in #2184, and released as a part of [v0.2.6](https://github.com/vyperlang/vyper/releases/tag/v0.2.6).

Text from GitHub Advisory Database

Affected versions 24

  • vyper, pip< 0.2.6GitHub
  • vyper, PyPIfrom first release, fixed in 0.2.6OSV
  • vyper, PyPI0.1.0b1OSV
  • vyper, PyPI0.1.0b10OSV
  • vyper, PyPI0.1.0b11OSV
  • vyper, PyPI0.1.0b12OSV
  • vyper, PyPI0.1.0b13OSV
  • vyper, PyPI0.1.0b14OSV
  • vyper, PyPI0.1.0b15OSV
  • vyper, PyPI0.1.0b16OSV
  • vyper, PyPI0.1.0b17OSV
  • vyper, PyPI0.1.0b2OSV
  • vyper, PyPI0.1.0b3OSV
  • vyper, PyPI0.1.0b4OSV
  • vyper, PyPI0.1.0b5OSV
  • vyper, PyPI0.1.0b6OSV
  • vyper, PyPI0.1.0b7OSV
  • vyper, PyPI0.1.0b8OSV
  • vyper, PyPI0.1.0b9OSV
  • vyper, PyPI0.2.1OSV
  • vyper, PyPI0.2.2OSV
  • vyper, PyPI0.2.3OSV
  • vyper, PyPI0.2.4OSV
  • vyper, PyPI0.2.5OSV

References 6