uw-imap is the University of Washington's IMAP and POP server daemons.
Improper bounds checking of user supplied data while parsing IMAP mailbox names can lead to overflowing the stack buffer.
Successful exploitation requires an authenticated IMAP user to request a malformed mailbox name. This can lead to execution of arbitrary code with the permissions of the IMAP server.
There are no known workarounds at this time.
All uw-imap users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=net-mail/uw-imap-2004g"