Shadow is a set of tools to deal with user accounts.
Multiple vulnerabilities have been discovered in Shadow. Please review the CVE identifiers referenced below for details.
A local attacker could possibly cause a Denial of Service condition, gain privileges via crafted input, or SIGKILL arbitrary processes.
There is no known workaround at this time.
All Shadow users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=sys-apps/shadow-4.4-r2"