(RHSA-2009:1116) Important: cyrus-imapd security update

The cyrus-imapd packages contain a high-performance mail server with IMAP,
POP3, NNTP, and SIEVE support.

It was discovered that the Cyrus SASL library (cyrus-sasl) does not always
reliably terminate output from the sasl_encode64() function used by
programs using this library. The Cyrus IMAP server (cyrus-imapd) relied on
this function’s output being properly terminated. Under certain conditions,
improperly terminated output from sasl_encode64() could, potentially, cause
cyrus-imapd to crash, disclose portions of its memory, or lead to SASL
authentication failures. (CVE-2009-0688)

Users of cyrus-imapd are advised to upgrade to these updated packages,
which resolve this issue. After installing the update, cyrus-imapd will be
restarted automatically.