CVE-2023-31146

Public Exploit
Vyper vulnerable to OOB DynArray access when array is on both LHS and RHS of an assignment

Description

Vyper is a Pythonic smart contract language for the Ethereum virtual machine. Prior to version 0.3.8, during codegen, the length word of a dynarray is written before the data, which can result in out-of-bounds array access in the case where the dynarray is on both the lhs and rhs of an assignment. The issue can cause data corruption across call frames. The expected behavior is to revert due to out-of-bounds array access. Version 0.3.8 contains a patch for this issue.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.17%
Vendor Advisory github.com
Affected: vyperlang vyper
Published at:
Updated at:

References

Link Tags
https://github.com/vyperlang/vyper/security/advisories/GHSA-3p37-3636-q8wv exploit vendor advisory
https://github.com/vyperlang/vyper/commit/4f8289a81206f767df1900ac48f485d90fc87edb patch

Frequently Asked Questions

What is the severity of CVE-2023-31146?
CVE-2023-31146 has been scored as a high severity vulnerability.
How to fix CVE-2023-31146?
To fix CVE-2023-31146, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-31146 being actively exploited in the wild?
It is possible that CVE-2023-31146 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-31146?
CVE-2023-31146 affects vyperlang vyper.
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