# CVE-2025-6395: GnuTLS NULL pointer dereference in _gnutls_figure_common_ciphersuite

Source: https://junglewise.ai/threats/cve-2025-6395-gnutls-null-pointer-dereference-in-gnutls-figure-common  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-07-10. Updated: 2026-06-25  
License: CC BY 4.0 with a link back

CVE-2025-6395 · Severity: medium · CVSS 6.5 · Published 2025-07-10

GnuTLS is a widely used security library that enables encrypted communications for Linux systems and various applications. A flaw was found that could allow an attacker to crash services using this library by sending specifically crafted network traffic during the initial connection setup. This results in a denial-of-service, potentially taking down web servers, VPNs, or other secure communication channels.

Technologies: [Red Hat Enterprise Linux 10](https://junglewise.ai/threats/technologies/enterprise-linux-10), [Red Hat Enterprise Linux 8](https://junglewise.ai/threats/technologies/enterprise-linux-8), [Red Hat Enterprise Linux 9](https://junglewise.ai/threats/technologies/enterprise-linux-9). Vendors: [Red Hat](https://junglewise.ai/threats/vendors/red-hat).

## Quick answers

**Is CVE-2025-6395 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-6395 being exploited in the wild.

**How severe is CVE-2025-6395?** Medium severity, with a CVSS score of 6.5, published 10 July 2025.

**Which products and versions are affected?** Red Hat Enterprise Linux 10 < 3.8.9-9.el10_0.14; Red Hat Enterprise Linux 8 < 3.6.16-8.el8_10.4; Red Hat Enterprise Linux 9 < 3.8.3-6.el9_6.2.

**Is there a fix for CVE-2025-6395?** A patch was published on 2025-07-08: GnuTLS 3.8.10 released with fix Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2025-6395 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2025-6395?** Check whether you run Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8 or Red Hat Enterprise Linux 9 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A NULL pointer dereference vulnerability exists in GnuTLS within the _gnutls_figure_common_ciphersuite() function. The flaw is triggered during the negotiation of common ciphersuites between a client and server. An unauthenticated remote attacker can exploit this by sending a specially crafted handshake, causing the application linked against GnuTLS to terminate unexpectedly. While the attack vector is network-based, the complexity is rated as high, likely due to specific preconditions required in the ciphersuite selection logic. The issue is addressed in GnuTLS version 3.8.10 and various vendor-specific patches.

## Affected products

- GnuTLS GnuTLS < 3.8.10
- Red Hat Red Hat Enterprise Linux 8 < 3.6.16-8.el8_10.4
- Red Hat Red Hat Enterprise Linux 9 < 3.8.3-6.el9_6.2
- Red Hat Red Hat Enterprise Linux 10 < 3.8.9-9.el10_0.14

## Timeline

- 2025-07-08: patched: GnuTLS 3.8.10 released with fix
- 2025-07-10: disclosed: NVD publication date
- 2025-09-17: advisory: Red Hat security advisories issued

## References

- [https://www.gnutls.org/](https://www.gnutls.org/)
- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)
- [https://catalog.redhat.com/software/containers/](https://catalog.redhat.com/software/containers/)
- [https://access.redhat.com/errata/RHSA-2025:16115](https://access.redhat.com/errata/RHSA-2025:16115)
- [https://access.redhat.com/errata/RHSA-2025:16116](https://access.redhat.com/errata/RHSA-2025:16116)
- [https://access.redhat.com/errata/RHSA-2025:17181](https://access.redhat.com/errata/RHSA-2025:17181)
- [https://access.redhat.com/errata/RHSA-2025:17348](https://access.redhat.com/errata/RHSA-2025:17348)

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