sudo allows a system administrator to give users the ability to run commands as other users.
In certain password input handling, sudo incorrectly assumes the password input is at least nine bytes in size, leading to a heap buffer overread.
In the worst case, the heap buffer overread can result in the denial of service of the sudo process.
There is no known workaround at this time.
All sudo users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=app-admin/sudo-1.9.12-r1"