(RHSA-2017:0574) Moderate: gnutls security, bug fix, and enhancement update

The gnutls packages provide the GNU Transport Layer Security (GnuTLS) library, which implements cryptographic algorithms and protocols such as SSL, TLS, and DTLS.

The following packages have been upgraded to a later upstream version: gnutls (2.12.23). (BZ#1321112, BZ#1326073, BZ#1415682, BZ#1326389)

Security Fix(es):

• A denial of service flaw was found in the way the TLS/SSL protocol defined processing of ALERT packets during a connection handshake. A remote attacker could use this flaw to make a TLS/SSL server consume an excessive amount of CPU and fail to accept connections form other clients. (CVE-2016-8610)

• Multiple flaws were found in the way gnutls processed OpenPGP certificates. An attacker could create specially crafted OpenPGP certificates which, when parsed by gnutls, would cause it to crash. (CVE-2017-5335, CVE-2017-5336, CVE-2017-5337)

Additional Changes:

For detailed information on changes in this release, see the Red Hat Enterprise Linux 6.9 Release Notes and Red Hat Enterprise Linux 6.9 Technical Notes linked from the References section.