# PYSEC-2022-43153 - Wasm3 0.5.0 has a heap-based buffer overflow in NewCodePage in m3_code.c (called indirectly from Compile_BranchTable in m3_compile.c).

Source: https://junglewise.ai/threats/pysec-2022-43153-wasm3-0-5-0-has-a-heap-based-buffer-overflow-in-bdd144ab  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-04-16  
License: CC BY 4.0 with a link back

Severity: low · CVSS 3.1 · Published 2022-04-16

Wasm3 0.5.0 has a heap-based buffer overflow in NewCodePage in m3_code.c (called indirectly from Compile_BranchTable in m3_compile.c).

Technologies: [pywasm3 (PyPI)](https://junglewise.ai/threats/technologies/pywasm3). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** Low severity, with a CVSS score of 3.1, published 16 April 2022.

**Which products and versions are affected?** pywasm3 (PyPI) ECOSYSTEM:introduced=0.

**Is there a fix for This vulnerability?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**Am I affected?** Check whether you run pywasm3 (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.

## Affected products

- pywasm3 (PyPI) ECOSYSTEM:introduced=0

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- [wasm3 pywasm3 use-after-free in ForEachModule](https://junglewise.ai/threats/cve-2024-27530-wasm3-pywasm3-use-after-free-in-foreachmodule)
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- [PYSEC-2024-303 - wasm3 139076a is vulnerable to Denial of Service (DoS).](https://junglewise.ai/threats/cve-2024-27527-pysec-2024-303-wasm3-139076a-is-vulnerable-to-denial-of-service)