vyper performs double eval of raw_args in create_from_blueprint
Summary
Using the create_from_blueprint builtin can result in a double eval vulnerability when raw_args=True and the args argument has side-effects.
A contract search was performed and no vulnerable contracts were found in production. In particular, the raw_args variant of create_from_blueprint was not found to be used in production.
Details
It can be seen that the _build_create_IR function of the create_from_blueprint builtin doesn't cache the mentioned args argument to the stack: https://github.com/vyperlang/vyper/blob/cedf7087e68e67c7bfbd47ae95dcb16b81ad2e02/vyper/builtins/functions.py#L1847
As such, it can be evaluated multiple times (instead of retrieving the value from the stack).
PoC
The vulnerability is demonstrated in the following boa test:
src1 = """
c: uint256
"""
deployer = """
created_address: public(address)
deployed: public(uint256)
@external
def get() -> Bytes[32]:
self.deployed += 1
return b''
@external
def create_(target: address):
self.created_address = create_from_blueprint(target, raw_call(self, method_id("get()"), max_outsize=32), raw_args=True, code_offset=3)
"""
Factory = b.loads_partial(src1)
c = Factory.deploy_as_blueprint()
c2 = b.loads(deployer, b'')
c2.create_(c)
c2.deployed()The output of c2.deployed() is 2 although create_ was called only once and the value was initialized to 0.
Patches
Patched in https://github.com/vyperlang/vyper/pull/3976.
Impact
No vulnerable production contracts were found. Additionally, double evaluation of side-effects should be easily discoverable in client tests. As such, the impact is low.
Software afectado
Haz clic en una tecnología para ver todas sus vulnerabilidades.
| Plataforma | Paquete | Versiones vulnerables | Corregida en |
|---|---|---|---|
| Python (PyPI) | vyper | < 0.4.0 | 0.4.0 |
Referencias
- https://github.com/vyperlang/vyper/security/advisories/GHSA-3whq-64q2-qfj6
- https://github.com/vyperlang/vyper/blob/cedf7087e68e67c7bfbd47ae95dcb16b81ad2e02/vyper/builtins/functions.py#L1847
- https://github.com/advisories/GHSA-3whq-64q2-qfj6
- https://nvd.nist.gov/vuln/detail/CVE-2024-32647
- https://github.com/pypa/advisory-database/tree/main/vulns/vyper/PYSEC-2024-208.yaml
- https://github.com/vyperlang/vyper
- Vector CVSS
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N- Debilidad (CWE)
CWE-95- Plataforma
- Python (PyPI)
- Paquete
vyper- Publicada
- 25.04.2024
- Actualizado
- 11.10.2026 12:20
Fuentes y licencias
OSV / GitHub Advisory Database - PYSEC-2024-208 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-3whq-64q2-qfj6 - CC BY 4.0
Historial de vulnerabilidades: vyper
Todas las vulnerabilidades publicadas de este paquete (Python (PyPI)), de la más reciente a la más antigua. Muestra si es un fallo aislado o un paquete que hay que vigilar.
- Entradas en total
- 47
- Primera → última
- 03.2020 10.2026
- Sin corrección
- 5
- Explotada en ataques
- 0
Distribución por gravedad
- Crítica 3
- Alta 14
- Media 20
- Baja 10
Divulgaciones por año
- 2020: 1
- 2021: 5
- 2022: 4
- 2023: 14
- 2024: 14
- 2025: 6
- 2026: 3
-
vyper performs double eval of raw_args in create_from_blueprint esta entrada
Identifica las vulnerabilidades de tu aplicación
Con la integración de DockRay y el inventario de software activado, DockRay compara las versiones notificadas de los componentes con las vulnerabilidades conocidas y avisa de las coincidencias confirmadas. La cobertura depende de la tecnología compatible y de los avisos disponibles.