# CVE-2024-24564: Vyper's `extract32` can ready dirty memory

Source: https://junglewise.ai/threats/cve-2024-24564-vyper-s-extract32-can-ready-dirty-memory  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2024-02-26  
License: CC BY 4.0 with a link back

CVE-2024-24564 · Severity: low · CVSS 3.1 · Published 2024-02-26

Vyper is a pythonic Smart Contract Language for the ethereum virtual machine. When using the built-in `extract32(b, start)`, if the `start` index provided has for side effect to update `b`, the byte array to extract `32` bytes from, it could be that some dirty memory is read and returned by `extract32`. This vulnerability is fixed in 0.4.0.

Technologies: [vyper (PyPI)](https://junglewise.ai/threats/technologies/vyper). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2024-24564 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2024-24564 being exploited in the wild.

**How severe is CVE-2024-24564?** Low severity, with a CVSS score of 3.1, published 26 February 2024.

**Which products and versions are affected?** vyper (PyPI) ECOSYSTEM:introduced=0,fixed=0.4.0, GIT:introduced=0,fixed=3d9c537142fb99b2672f21e2057f5f202cde194f|ECOSYSTEM:introduced=0,fixed=0.4.0.

**Is there a fix for CVE-2024-24564?** Yes. vyper (PyPI): upgrade to 0.4.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2024-24564?** Check whether you run vyper (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- vyper (PyPI): upgrade to 0.4.0 or later

  ```sh
  pip install "vyper>=0.4.0"
  ```


## Affected products

- vyper (PyPI) ECOSYSTEM:introduced=0,fixed=0.4.0, GIT:introduced=0,fixed=3d9c537142fb99b2672f21e2057f5f202cde194f|ECOSYSTEM:introduced=0,fixed=0.4.0

## Identifiers

- CVE-2024-24564
- GHSA-4hwq-4cpm-8vmx
- PYSEC-2024-205

## Related threats

- [Vyper memory corruption in nested function calls and tuples](https://junglewise.ai/threats/vyper-memory-corruption-using-function-calls-within-tuples-nested-calls-c0689acb)
- [Vyper stack corruption in complex type argument passing](https://junglewise.ai/threats/vyper-call-stack-corruption-when-passing-complex-type-containing-non-3deb0c30)
- [Vyper return statement in nested for loops causes revert](https://junglewise.ai/threats/vyper-return-inside-for-loop-more-than-1-level-deep-ee8a193d)
- [PYSEC-2026-2028 - Vyper's `slice()` may elide side-effects when output length is 0](https://junglewise.ai/threats/cve-2025-47774-vyper-s-slice-may-elide-side-effects-when-output-length-is-0)
- [PYSEC-2026-2029 - Vyper's `concat()` builtin may elide side-effects for zero-length arguments](https://junglewise.ai/threats/cve-2025-47285-vyper-s-concat-builtin-may-elide-side-effects-for-zero-length)