(RHSA-2008:0489) Critical: gnutls security update

The GnuTLS Library provides support for cryptographic algorithms and
protocols such as TLS. GnuTLS includes libtasn1, a library developed for
ASN.1 structures management that includes DER encoding and decoding.

Flaws were found in the way GnuTLS handles malicious client connections. A
malicious remote client could send a specially crafted request to a service
using GnuTLS that could cause the service to crash. (CVE-2008-1948,
CVE-2008-1949, CVE-2008-1950)

We believe it is possible to leverage the flaw CVE-2008-1948 to execute
arbitrary code but have been unable to prove this at the time of releasing
this advisory. Red Hat Enterprise Linux 5 includes applications, such as
CUPS, that would be directly vulnerable to any such an exploit, however.
Consequently, we have assigned it critical severity.

Users of GnuTLS are advised to upgrade to these updated packages, which
contain a backported patch that corrects these issues.