{"id":"UBUNTU-CVE-2020-13777","details":"GnuTLS 3.6.x before 3.6.14 uses incorrect cryptography for encrypting a session ticket (a loss of confidentiality in TLS 1.2, and an authentication bypass in TLS 1.3). The earliest affected version is 3.6.4 (2018-09-24) because of an error in a 2018-09-18 commit. Until the first key rotation, the TLS server always uses wrong data in place of an encryption key derived from an application.","modified":"2026-04-22T14:03:16.087488Z","published":"2020-06-04T07:15:00Z","related":["USN-4384-1"],"upstream":["CVE-2020-13777"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-13777"},{"type":"REPORT","url":"https://gnutls.org/security-new.html#GNUTLS-SA-2020-06-03"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4384-1"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2020-13777"}],"affected":[{"package":{"name":"gnutls28","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/gnutls28@3.6.13-2ubuntu1.1?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.6.13-2ubuntu1.1"}]}],"versions":["3.6.9-5ubuntu1","3.6.9-5ubuntu2","3.6.10-5","3.6.11.1-2","3.6.11.1-2ubuntu2","3.6.13-2ubuntu1"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_version":"3.6.13-2ubuntu1.1","binary_name":"gnutls-bin"},{"binary_name":"guile-gnutls","binary_version":"3.6.13-2ubuntu1.1"},{"binary_version":"3.6.13-2ubuntu1.1","binary_name":"libgnutls-dane0"},{"binary_name":"libgnutls-openssl27","binary_version":"3.6.13-2ubuntu1.1"},{"binary_name":"libgnutls30","binary_version":"3.6.13-2ubuntu1.1"},{"binary_name":"libgnutlsxx28","binary_version":"3.6.13-2ubuntu1.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-13777.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"},{"type":"Ubuntu","score":"high"}]}