mod_fcgid is a binary-compatible alternative to mod_fastcgi with better process management.
Multiple vulnerabilities have been found in mod_fcgid:
A local attacker could possibly execute arbitrary code with the privileges of the process or cause a Denial of Service condition. Furthermore, a remote attacker could send specially crafted HTTP requests, possibly resulting in a Denial of Service condition.
There is no known workaround at this time.
All mod_fcgid users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=www-apache/mod_fcgid-2.3.7"