USN-3999-1: GnuTLS vulnerabilities

30 May 2019

Several security issues were fixed in GnuTLS.

Releases

Packages

  • 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,
resulting in a denial of service, or possibly execute arbitrary code. This
issue only affected Ubuntu 18.10 and Ubuntu 19.04. (CVE-2019-3836)

Update instructions

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

Ubuntu 19.04
Ubuntu 18.10
Ubuntu 18.04
Ubuntu 16.04

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