Cyrus-SASL is an implementation of the Simple Authentication and Security Layer.
Cyrus-SASL contains an unspecified vulnerability in the DIGEST-MD5 process that could lead to a Denial of Service.
An attacker could possibly exploit this vulnerability by sending specially crafted data stream to the Cyrus-SASL server, resulting in a Denial of Service even if the attacker is not able to authenticate.
There is no known workaround at this time.
All Cyrus-SASL users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=dev-libs/cyrus-sasl-2.1.21-r2"