A vulnerability was discovered and corrected in krb5:

The merge_authdata function in kdc_authdata.c in the Key Distribution
Center (KDC) in MIT Kerberos 5 (aka krb5) 1.8.x before 1.8.4 does
not properly manage an index into an authorization-data list, which
allows remote attackers to cause a denial of service (daemon crash),
or possibly obtain sensitive information, spoof authorization,
or execute arbitrary code, via a TGS request, as demonstrated by a
request from a Windows Active Directory client (CVE-2010-1322).

The updated packages have been patched to correct this issue.