plugins/preauth/pkinit/pkinitcryptoopenssl.c in MIT Kerberos 5 (aka krb5) through 1.15.2 mishandles Distinguished Name (DN) fields, which allows remote attackers to execute arbitrary code or cause a denial of service (buffer overflow and application crash) in situations involving untrusted X.509 data, related to the getmatchingdata and X509NAMEonelineex functions. NOTE: this has security relevance only in use cases outside of the MIT Kerberos distribution, e.g., the use of getmatching_data in KDC certauth plugin code that is specific to Red Hat.