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vulnerability

Oracle Linux: CVE-2020-13777: ELSA-2020-2637: gnutls security update (IMPORTANT)

Severity
6
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:N)
Published
Jun 3, 2020
Added
Jul 22, 2020
Modified
Dec 3, 2025

Description

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.
A flaw was found in GnuTLS, in versions starting from 3.6.4, where it does not session the ticket encryption key in a secure fashion by the application which is connecting. This flaw allows an attacker to craft a man-in-the-middle-attack, with the ability to bypass the TLS1.3 authentication and also recover older conversations when TLS1.2 is in use. The highest threat to this flaw is to confidentiality and integrity.

Solutions

oracle-linux-upgrade-gnutlsoracle-linux-upgrade-gnutls-coracle-linux-upgrade-gnutls-daneoracle-linux-upgrade-gnutls-develoracle-linux-upgrade-gnutls-utils
Title
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