Usermin is a web-based administration tool for Unix. It supports a wide range of user applications including configuring mail forwarding, setting up SSH or reading mail.
Usermin contains two security vulnerabilities. One fails to properly sanitize email messages that contain malicious HTML or script code and the other could allow an attacker to lock out a valid user by sending an invalid username and password.
By sending a specially crafted e-mail, an attacker can execute arbitrary scripts running in the context of the victim's browser. This can be lead to cookie theft and potentially to compromise of user accounts. Furthermore, an attacker could lock out legitimate users by sending invalid login information.
There is no known workaround at this time. All users are encouraged to upgrade to the latest available version.
Usermin users should upgrade to the latest version:
# emerge sync
# emerge -pv ">=app-admin/usermin-1.080"
# emerge ">=app-admin/usermin-1.080"