{"id":"CVE-2020-24659","title":"An issue was discovered in GnuTLS before 3.6.15","summary":"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 happe…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-476","CWE-787"],"vendor":"gnu","product":"gnutls","affected":["gnutls < 3.6.15","fedora = 32","fedora = 33","leap = 15.1","leap = 15.2","ubuntu_linux = 20.04"],"patched":["gnutls 3.6.15"],"published":"2020-09-04","updated":"2026-10-14","sourceUpdated":"2026-10-14T10:17:32.493","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2020-24659","references":[{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00054.html","label":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00060.html","label":"cve@mitre.org"},{"url":"https://gitlab.com/gnutls/gnutls/-/issues/1071","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/62BUAI4FQQLG6VTKRT7SUZPGJJ4NASQ3/","label":"cve@mitre.org"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AWN56FDLQQXT2D2YHNI4TYH432TDMQ7N/","label":"cve@mitre.org"},{"url":"https://security.gentoo.org/glsa/202009-01","label":"cve@mitre.org"},{"url":"https://security.netapp.com/advisory/ntap-20200911-0006/","label":"cve@mitre.org"},{"url":"https://usn.ubuntu.com/4491-1/","label":"cve@mitre.org"},{"url":"https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-09-04","label":"cve@mitre.org"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00054.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00060.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://gitlab.com/gnutls/gnutls/-/issues/1071","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/62BUAI4FQQLG6VTKRT7SUZPGJJ4NASQ3/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AWN56FDLQQXT2D2YHNI4TYH432TDMQ7N/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/202009-01","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20200911-0006/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/4491-1/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-09-04","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-398330.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd"],"epss":0.0373,"epssPercentile":0.8959,"ingestedAt":"2026-10-14T10:25:41.180Z","slug":"CVE-2020-24659","body":"## Overview\n\nAn 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.\n\n## Affected\n\n- `gnutls < 3.6.15`\n- `fedora = 32`\n- `fedora = 33`\n- `leap = 15.1`\n- `leap = 15.2`\n- `ubuntu_linux = 20.04`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `gnutls 3.6.15`","depth":"twilight","depthScore":42,"depthScoreParts":{"impact":41.3,"likelihood":0.7,"exploitation":0,"ransomware":0},"changes":[]}