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.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-09-04 Vendor Advisory
- https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-09-04 Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 7.5 · gnu, fedoraproject, opensuseNVD modified 2026-10-14 10:17
Affected (CPE criteria) 6
cpe:2.3:a:gnu:gnutls:*:*:*:*:*:*:*:*cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
References 19
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00054.html Mailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00060.html Mailing List, Third Party Advisory
- https://gitlab.com/gnutls/gnutls/-/issues/1071 Exploit, Issue Tracking, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/62BUAI4FQQLG6VTKRT7SUZPGJJ4NASQ3/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AWN56FDLQQXT2D2YHNI4TYH432TDMQ7N/
- https://security.gentoo.org/glsa/202009-01 Third Party Advisory
- https://security.netapp.com/advisory/ntap-20200911-0006/ Third Party Advisory
- https://usn.ubuntu.com/4491-1/ Third Party Advisory
- https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-09-04 Vendor Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00054.html Mailing List, Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00060.html Mailing List, Third Party Advisory
- https://gitlab.com/gnutls/gnutls/-/issues/1071 Exploit, Issue Tracking, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/62BUAI4FQQLG6VTKRT7SUZPGJJ4NASQ3/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AWN56FDLQQXT2D2YHNI4TYH432TDMQ7N/
- https://security.gentoo.org/glsa/202009-01 Third Party Advisory
- https://security.netapp.com/advisory/ntap-20200911-0006/ Third Party Advisory
- https://usn.ubuntu.com/4491-1/ Third Party Advisory
- https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-09-04 Vendor Advisory
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html