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.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | gnutls28 | 3.6.15-1 | — |
| Debian 13 | gnutls28 | 3.6.15-1 | — |
| Debian 12 | gnutls28 | 3.6.15-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | gnutls28 | 3.6.13-2ubuntu1.3 | USN-4491-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | gnutls +4 | 3.6.14-7.el8_3 | RHSA-2020:5483 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP3 | gnutls | 3.6.7-14.4.1 | SUSE-SU-2020:2864-2 |
| SLES 15 SP2 | gnutls | 3.6.7-14.4.1 | SUSE-SU-2020:2864-1 |
| SLES 15 SP1 | gnutls | 3.6.7-6.34.1 | SUSE-SU-2020:2988-1 |
| SLES 15 | gnutls | 3.6.7-6.34.1 | SUSE-SU-2020:2988-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 | gnutls | 3.6.7-6.34.1 | SUSE-SU-2020:2988-1 |
| SLE HPC 15 | gnutls | 3.6.7-6.34.1 | SUSE-SU-2020:2988-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.2 | gnutls | 3.6.7-lp152.9.3.2 | openSUSE-SU-2020:1743-1 |
| openSUSE Leap 15.1 | gnutls | 3.6.7-lp151.2.21.1 | openSUSE-SU-2020:1724-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | gnutls | 3.6.15-r0 | — |
| Alpine v3.23 | gnutls | 3.6.15-r0 | — |
| Alpine v3.22 | gnutls | 3.6.15-r0 | — |
| Alpine v3.21 | gnutls | 3.6.15-r0 | — |
| Alpine v3.20 | gnutls | 3.6.15-r0 | — |
Show 11 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | gnutls | 3.6.15-r0 | — |
| Alpine v3.18 | gnutls | 3.6.15-r0 | — |
| Alpine v3.17 | gnutls | 3.6.15-r0 | — |
| Alpine v3.16 | gnutls | 3.6.15-r0 | — |
| Alpine v3.15 | gnutls | 3.6.15-r0 | — |
| Alpine v3.14 | gnutls | 3.6.15-r0 | — |
| Alpine v3.13 | gnutls | 3.6.15-r0 | — |
| Alpine v3.12 | gnutls | 3.6.15-r0 | — |
| Alpine v3.11 | gnutls | 3.6.15-r0 | — |
| Alpine v3.10 | gnutls | 3.6.15-r0 | — |
| Alpine v3.9 | gnutls | 3.6.15-r0 | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | gnutls | 3.6.14-5 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | gnutls +4 | 3.6.14-7.el8_3 | ELSA-2020-5483 |
Advisories 12
- RHSA-2020:5483 Red Hat Security Advisory: gnutls security and bug fix update Red Hat Security Advisories (RHSA) · Oct 15, 2026
- SSA-398330 SSA-398330: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.5 Siemens ProductCERT · Oct 13, 2026
- WID-SEC-2025-0227 IBM QRadar SIEM: Mehrere Schwachstellen BSI CERT-Bund (WID) · Aug 11, 2026
- USN-4491-1 gnutls28 vulnerability Ubuntu Security Notices (USN) · Apr 22, 2026
- SUSE-SU-2020:2864-2 Security update for gnutls SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2988-1 Security update for gnutls SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:1743-1 Security update for gnutls SUSE / openSUSE Security Updates · Feb 4, 2026
- ICSA-23-348-10 Siemens SIMATIC S7-1500 CISA ICS & IT advisories · Aug 12, 2025
- VDE-2022-010 PHOENIX CONTACT: Multiple Linux component vulnerabilities fixed in latest AXC F x152 LTS release CERT@VDE · May 22, 2025
- openSUSE-SU-2020:1724-1 Security update for gnutls SUSE / openSUSE Security Updates · May 7, 2025
- SUSE-SU-2020:2864-1 Security update for gnutls SUSE / openSUSE Security Updates · May 2, 2025
- ELSA-2020-5483 Moderate: gnutls security and bug fix update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Dec 21, 2020
References
- https://gitlab.com/gnutls/gnutls/-/issues/1071
- https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-09-04
- GLSA-202009-01 vendor-advisory
- https://security.netapp.com/advisory/ntap-20200911-0006/
- FEDORA-2020-0ab6656303 vendor-advisory
- USN-4491-1 vendor-advisory
- FEDORA-2020-de51ee7cc9 vendor-advisory
- openSUSE-SU-2020:1724 vendor-advisory
- openSUSE-SU-2020:1743 vendor-advisory