CVE-2023-31146 – vyper

Package

Manager: pip
Name: vyper
Vulnerable Version: >=0 <0.3.8

Severity

Level: High

CVSS v3.1: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

EPSS: 0.00165 pctl0.37982

Details

Vyper vulnerable to OOB DynArray access when array is on both LHS and RHS of an assignment ### Impact during codegen, the length word of a dynarray is written before the data, which can result in OOB array access in the case where the dynarray is on both the lhs and rhs of an assignment. here is a minimal example producing the issue: ```vyper a:DynArray[uint256,3] @external def test() -> DynArray[uint256,3]: self.a = [1,2,3] self.a = empty(DynArray[uint256,3]) self.a = [self.a[0],self.a[1],self.a[2]] return self.a # return [1,2,3] ``` and here is an example demonstrating the issue can cause data corruption across call frames: ```vyper @external def test() -> DynArray[uint256,3]: self.a() return self.b() # return [1,2,3] @internal def a(): a: uint256 = 0 b: uint256 = 1 c: uint256 = 2 d: uint256 = 3 @internal def b() -> DynArray[uint256,3]: a: DynArray[uint256,3] = empty(DynArray[uint256,3]) a = [a[0],a[1],a[2]] return a ``` examples involving append and pop: ```vyper @internal def foo(): c: DynArray[uint256, 1] = [] c.append(c[0]) ``` ```vyper @internal def foo(): c: DynArray[uint256, 1] = [1] c[0] = c.pop() ``` the expected behavior in all of the above cases is to revert due to oob array access. ### Patches patched in 4f8289a81206f767df1900ac48f485d90fc87edb ### 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?_

Metadata

Created: 2023-05-12T20:21:54Z
Modified: 2024-11-19T16:32:12Z
Source: https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/05/GHSA-3p37-3636-q8wv/GHSA-3p37-3636-q8wv.json
CWE IDs: ["CWE-787"]
Alternative ID: GHSA-3p37-3636-q8wv
Finding: F111
Auto approve: 1