pysec-2024-246
Vulnerability from pysec
Vyper is a pythonic Smart Contract Language for the Ethereum virtual machine. Starting in version 0.3.8 and prior to version 0.4.0b1, when looping over a range of the form range(start, start + N), if start is negative, the execution will always revert. This issue is caused by an incorrect assertion inserted by the code generation of the range stmt.parse_For_range(). The issue arises when start is signed, instead of using sle, le is used and start is interpreted as an unsigned integer for the comparison. If it is a negative number, its 255th bit is set to 1 and is hence interpreted as a very large unsigned integer making the assertion always fail. Any contract having a range(start, start + N) where start is a signed integer with the possibility for start to be negative is affected. If a call goes through the loop while supplying a negative start the execution will revert. Version 0.4.0b1 fixes the issue.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "vyper",
"purl": "pkg:pypi/vyper"
},
"ranges": [
{
"events": [
{
"introduced": "0.3.8"
},
{
"fixed": "0.4.0b1"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"0.3.10",
"0.3.10rc1",
"0.3.10rc2",
"0.3.10rc3",
"0.3.10rc4",
"0.3.10rc5",
"0.3.8",
"0.3.9"
]
}
],
"aliases": [
"CVE-2024-32481"
],
"details": "Vyper is a pythonic Smart Contract Language for the Ethereum virtual machine. Starting in version 0.3.8 and prior to version 0.4.0b1, when looping over a `range` of the form `range(start, start + N)`, if `start` is negative, the execution will always revert. This issue is caused by an incorrect assertion inserted by the code generation of the range `stmt.parse_For_range()`. The issue arises when `start` is signed, instead of using `sle`, `le` is used and `start` is interpreted as an unsigned integer for the comparison. If it is a negative number, its 255th bit is set to `1` and is hence interpreted as a very large unsigned integer making the assertion always fail. Any contract having a `range(start, start + N)` where `start` is a signed integer with the possibility for `start` to be negative is affected. If a call goes through the loop while supplying a negative `start` the execution will revert. Version 0.4.0b1 fixes the issue.",
"id": "PYSEC-2024-246",
"modified": "2025-05-05T19:21:20.899426+00:00",
"published": "2024-04-25T17:15:50+00:00",
"references": [
{
"type": "ADVISORY",
"url": "https://github.com/vyperlang/vyper/security/advisories/GHSA-ppx5-q359-pvwj"
},
{
"type": "EVIDENCE",
"url": "https://github.com/vyperlang/vyper/security/advisories/GHSA-ppx5-q359-pvwj"
},
{
"type": "FIX",
"url": "https://github.com/vyperlang/vyper/commit/3de1415ee77a9244eb04bdb695e249d3ec9ed868"
},
{
"type": "FIX",
"url": "https://github.com/vyperlang/vyper/commit/5319cfbe14951e007ccdb323257e5ada869b35d5"
},
{
"type": "WEB",
"url": "https://github.com/vyperlang/vyper/blob/9136169468f317a53b4e7448389aa315f90b95ba/vyper/codegen/stmt.py#L286-L287"
}
],
"related": [
"GHSA-ppx5-q359-pvwj",
"GHSA-ppx5-q359-pvwj"
],
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
"type": "CVSS_V3"
}
]
}
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.