GHSA-vxmm-cwh2-q762

Suggest an improvement
Source
https://github.com/advisories/GHSA-vxmm-cwh2-q762
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/05/GHSA-vxmm-cwh2-q762/GHSA-vxmm-cwh2-q762.json
JSON Data
https://api.test.osv.dev/v1/vulns/GHSA-vxmm-cwh2-q762
Aliases
Published
2023-05-22T20:35:46Z
Modified
2024-11-19T16:48:14.071230Z
Severity
  • 3.7 (Low) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N CVSS Calculator
  • 6.3 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
Vyper's nonpayable default functions are sometimes payable
Details

Impact

in contracts with at least one regular nonpayable function, due to the callvalue check being inside of the selector section, it is possible to send funds to the default function by using less than 4 bytes of calldata, even if the default function is marked nonpayable. this applies to contracts compiled with vyper<=0.3.7.

# @version 0.3.7

# implicitly nonpayable
@external
def foo() -> uint256:
    return 1

# implicitly nonpayable
@external
def __default__():
    # could receive ether here
    pass

Patches

this was fixed by the removal of the global calldatasize check in https://github.com/vyperlang/vyper/commit/02339dfda0f3caabad142060d511d10bfe93c520.

Workarounds

don't use nonpayable default functions

Database specific 
{
    "nvd_published_at": "2023-05-19T20:15:09Z",
    "cwe_ids": [
        "CWE-670"
    ],
    "severity": "MODERATE",
    "github_reviewed": true,
    "github_reviewed_at": "2023-05-22T20:35:46Z"
}
References

Affected packages

PyPI / vyper

Package

Name
vyper
View open source insights on deps.dev
Purl
pkg:pypi/vyper

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
0.3.8

Affected versions

0.*

0.1.0b1
0.1.0b2
0.1.0b3
0.1.0b4
0.1.0b5
0.1.0b6
0.1.0b7
0.1.0b8
0.1.0b9
0.1.0b10
0.1.0b11
0.1.0b12
0.1.0b13
0.1.0b14
0.1.0b15
0.1.0b16
0.1.0b17
0.2.1
0.2.2
0.2.3
0.2.4
0.2.5
0.2.6
0.2.7
0.2.8
0.2.9
0.2.10
0.2.11
0.2.12
0.2.13
0.2.14
0.2.15
0.2.16
0.3.0
0.3.1
0.3.2
0.3.3
0.3.4
0.3.5
0.3.6
0.3.7