CVE-2023-32059: Vyper vulnerable to incorrect ordering of arguments for kwargs passed to internal calls
Impact
Internal calls to internal functions with more than 1 default argument are compiled incorrectly. Depending on the number of arguments provided in the call, the defaults are added not right-to-left, but left-to-right. If the types are incompatible, typechecking is bypassed. In the bar() function in the following code, self.foo(13) is compiled to self.foo(13,12) instead of self.foo(13,1337).
vyper @internal def foo(a:uint256 = 12, b:uint256 = 1337): pass
@internal def bar(): self.foo(13)
note that at the time of publication, the ability to pass kwargs to internal functions is an undocumented feature that does not seem to be widely used.
Patches patched in c3e68c302aa6e1429946473769dd1232145822ac
Workarounds Is there a way for users to fix or remediate the vulnerability without upgrading?
References Are there any links users can visit to find out more?
Other sources
Vyper is a Pythonic smart contract language for the Ethereum virtual machine. Prior to version 0.3.8, internal calls with default arguments are compiled incorrectly. Depending on the number of arguments provided in the call, the defaults are added not right-to-left, but left-to-right. If the types are incompatible, typechecking is bypassed. The ability to pass kwargs to internal functions is an undocumented feature that is not well known about. The issue is patched in version 0.3.8.
— MITRE
Affected Software
Remediation
Event History
Frequently Asked Questions
What is CVE-2023-32059?
CVE-2023-32059 is a vulnerability in the Vyper smart contract language for the Ethereum virtual machine where internal calls with default arguments are compiled incorrectly.
What is the severity of CVE-2023-32059?
The severity of CVE-2023-32059 is high with a CVSS score of 7.5.
How does CVE-2023-32059 affect Vyper?
CVE-2023-32059 affects Vyper versions prior to 0.3.8.
How can I fix CVE-2023-32059 in Vyper?
To fix CVE-2023-32059, update Vyper to version 0.3.8 or later.
What is the CWE ID for CVE-2023-32059?
The CWE ID for CVE-2023-32059 is 683.