(krb5kdc): Double-free flaw by handling error messages upon receiving certain AS_REQ's (MITKRB5-SA-2011-003)

Double free vulnerability in the prepareerroras function in doasreq.c in the Key Distribution Center KDC in MIT Kerberos 5 aka krb5 1.7 through 1.9, when the PKINIT feature is enabled, allows remote attackers to cause a denial of service daemon crash or possibly execute arbitrary code via an edat...