CVE-2007-3149

sudo, when linked with MIT Kerberos 5 (krb5), does not properly check
whether a user can currently authenticate to Kerberos, which allows local
users to gain privileges, in a manner unintended by the sudo security
model, via certain KRB5_ environment variable settings. NOTE: another
researcher disputes this vulnerability, stating that the attacker must be
“a user, who can already log into your system, and can already use sudo.”