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.
References (9)
Core 9
Core References
Exploit, Issue Tracking, Third Party Advisory x_refsource_misc
https://gitlab.com/gnutls/gnutls/-/issues/1071
Vendor Advisory x_refsource_misc
https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-09-04
Third Party Advisory vendor-advisory
x_refsource_gentoo
https://security.gentoo.org/glsa/202009-01
Third Party Advisory x_refsource_confirm
https://security.netapp.com/advisory/ntap-20200911-0006/
Mailing List, Third Party Advisory vendor-advisory
x_refsource_fedora
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/62BUAI4FQQLG6VTKRT7SUZPGJJ4NASQ3/
Third Party Advisory vendor-advisory
x_refsource_ubuntu
https://usn.ubuntu.com/4491-1/
Mailing List, Third Party Advisory vendor-advisory
x_refsource_fedora
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AWN56FDLQQXT2D2YHNI4TYH432TDMQ7N/
Mailing List, Third Party Advisory vendor-advisory
x_refsource_suse
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00054.html
Mailing List, Third Party Advisory vendor-advisory
x_refsource_suse
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00060.html
Scores
CVSS v3
7.5
EPSS
0.0363
EPSS Percentile
88.0%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Details
CWE
CWE-476
CWE-787
Status
published
Products (6)
canonical/ubuntu_linux
20.04
fedoraproject/fedora
32
fedoraproject/fedora
33
gnu/gnutls
< 3.6.15
opensuse/leap
15.1
opensuse/leap
15.2
Published
Sep 04, 2020
Tracked Since
Feb 18, 2026