CVE-2023-46247

Vyper has incorrect storage layout for contracts containing large arrays

Description

Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Contracts containing large arrays might underallocate the number of slots they need by 1. Prior to v0.3.8, the calculation to determine how many slots a storage variable needed used `math.ceil(type_.size_in_bytes / 32)`. The intermediate floating point step can produce a rounding error if there are enough bits set in the IEEE-754 mantissa. Roughly speaking, if `type_.size_in_bytes` is large (> 2**46), and slightly less than a power of 2, the calculation can overestimate how many slots are needed by 1. If `type_.size_in_bytes` is slightly more than a power of 2, the calculation can underestimate how many slots are needed by 1. This issue is patched in version 0.3.8.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.34%
Third-Party Advisory github.com
Affected: vyperlang vyper
Published at:
Updated at:

References

Link Tags
https://github.com/vyperlang/vyper/security/advisories/GHSA-6m97-7527-mh74 third party advisory
https://github.com/vyperlang/vyper/commit/0bb7203b584e771b23536ba065a6efda457161bb patch
https://github.com/vyperlang/vyper/blob/6020b8bbf66b062d299d87bc7e4eddc4c9d1c157/vyper/semantics/validation/data_positions.py#L197 product

Frequently Asked Questions

What is the severity of CVE-2023-46247?
CVE-2023-46247 has been scored as a high severity vulnerability.
How to fix CVE-2023-46247?
To fix CVE-2023-46247, 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-2023-46247 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-46247 is being actively exploited. 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-2023-46247?
CVE-2023-46247 affects vyperlang vyper.
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