The Common UNIX Printing System (CUPS) is a cross-platform print spooler.
When printing to a SMB-shared printer requiring authentication, CUPS leaks the user name and password to a logfile.
A local user could gain knowledge of sensitive authentication data.
There is no known workaround at this time.
All CUPS users should upgrade to the latest version:
# emerge sync
# emerge -pv ">=net-print/cups-1.1.20-r3"
# emerge ">=net-print/cups-1.1.20-r3"