CVE-2023-30837

Storage allocation overflow vulnerability in Vyper (before version 0.3.8)

• CVSS 7.5
• CWE-789
• Design Defects
• Remote

Vyper is a pythonic smart contract language for the EVM. The storage allocator does not guard against allocation overflows in versions prior to 0.3.8. An attacker can overwrite the owner variable. This issue was fixed in version 0.3.8.

CVE

CVE-2023-30837

CWE

CWE-789

CVSS base score

7.5

Published

2023-05-08

OWASP

A04 Insecure Design

Orthogonal defect classification

Assignment

Code defect classification

Incorrect Assignment

Category

Design Defects

Subcategory

Inadequate Error Handling

Accessibility scope

Remote

Impact

Unauthorized Access

Fixed by upgrading

Yes

Solution

Update to Vyper version 0.3.8 or higher

owner: public(address)
data: public(uint256)

@public
def set_data(new_data: uint256):
    self.data = new_data

@public
def set_owner(new_owner: address):
    self.owner = new_owner

owner: public(address)
data: public(uint256)

@public
def set_data(new_data: uint256):
    assert new_data >= 0
    self.data = new_data

@public
def set_owner(new_owner: address):
    assert new_owner != ZERO_ADDRESS
    self.owner = new_owner

@misc{vaitp:cve202330837,
  title        = {{Storage allocation overflow vulnerability in Vyper (before version 0.3.8)}},
  author       = {Bogaerts, Fr\'ed\'eric and Ivaki, Naghmeh and Fonseca, Jos\'e},
  year         = {2023},
  note         = {VAITP Python Vulnerability Dataset, entry CVE-2023-30837},
  howpublished = {\url{https://netpack.pt/vaitp/vulnerability/CVE-2023-30837/}}
}