Ubuntu 19.04: USN-3999-1 Critical: GnuTLS Denial of Service

ubuntu

May 30, 2019

Several security issues were fixed in GnuTLS.

Summary

Several security issues were fixed in GnuTLS.

Software Description:

- gnutls28: GNU TLS library

Details:

Eyal Ronen, Kenneth G. Paterson, and Adi Shamir discovered that GnuTLS was

vulnerable to a timing side-channel attack known as the "Lucky Thirteen"

issue. A remote attacker could possibly use this issue to perform

plaintext-recovery attacks via analysis of timing data. This issue only

affected Ubuntu 16.04 LTS and Ubuntu 18.04 LTS. (CVE-2018-10844,

CVE-2018-10845, CVE-2018-10846)

Tavis Ormandy discovered that GnuTLS incorrectly handled memory when

verifying certain X.509 certificates. A remote attacker could use this

issue to cause GnuTLS to crash, resulting in a denial of service, or

possibly execute arbitrary code. This issue only affected Ubuntu 18.04 LTS,

Ubuntu 18.10, and Ubuntu 19.04. (CVE-2019-3829)

It was discovered that GnuTLS incorrectly handled certain post-handshake

messages. A remote attacker could use this issue to cause GnuTLS to crash,

...

Read the Full Advisory

Topics Covered

security advisory denial of service software update remote execution timing attack ubuntu gnutls

Update Instructions

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

Ubuntu 19.04:
  libgnutls30                     3.6.5-2ubuntu1.1

Ubuntu 18.10:
  libgnutls30                     3.6.4-2ubuntu1.2

Ubuntu 18.04 LTS:
  libgnutls30                     3.5.18-1ubuntu1.1

Ubuntu 16.04 LTS:
  libgnutls30                     3.4.10-4ubuntu1.5

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