You should refer to the README file which has some informations on how to secure your Miredo installation, depending on the version of the program.
To mitigate risks in case a security breach were to be found, Miredo normally drops all privileges before handling any data from the network. Note however that Miredo still has to be started by root.
Miredo uses the common nobody unprivileged user
in the default configuration.
Most third-party distributions change this to a separate user with no shell
for extra security.
If you compile Miredo yourself, you should do likewise.
When run as a Teredo client, Miredo still needs network administration privileges when running. That is implemented with a separate privileged process, which is in charge of updating the tunnel network device paramaters.
In case of remote compromise of the program, the attacker should, unfortunately, be able to disrupt IPv6 connectivity.
Here is the list of official security advisories for Miredo in reverse chronological order. High priority is assigned to items that poses an immediate threat. Low priority is assigned to items that are difficult to exploit, or have a minor potential impact. Null priority refers to security advisories that are present only for reference to external vulnerability reports that are not considered to be problematic.