A GnuTLS security update has been released for Ubuntu Linux 20.04 LTS and 19.10.

USN-4384-1: GnuTLS vulnerability

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Ubuntu Security Notice USN-4384-1
June 05, 2020

gnutls28 vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS
- Ubuntu 19.10

Summary:

GnuTLS could be made to expose sensitive information.

Software Description:
- gnutls28: GNU TLS library

Details:

It was discovered that GnuTLS incorrectly handled session ticket encryption
keys. A remote attacker could possibly use this issue to bypass
authentication or recover sensitive information.

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 20.04 LTS:
libgnutls30 3.6.13-2ubuntu1.1

Ubuntu 19.10:
libgnutls30 3.6.9-5ubuntu1.2

In general, a standard system update will make all the necessary changes.

References:
https://usn.ubuntu.com/4384-1
CVE-2020-13777

Package Information:
https://launchpad.net/ubuntu/+source/gnutls28/3.6.13-2ubuntu1.1
https://launchpad.net/ubuntu/+source/gnutls28/3.6.9-5ubuntu1.2