schpw.c in the kpasswd service in kadmind in MIT Kerberos 5 (aka krb5) before 1.11.3 does not properly validate UDP packets before sending responses, which allows remote attackers to cause a denial of service (CPU and bandwidth consumption) via a forged packet that triggers a communication loop, as demonstrated by krb_pingpong.nasl, a related issue to CVE-1999-0103.

The prep_reprocess_req function in do_tgs_req.c in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) before 1.10.5 does not properly perform service-principal realm referral, which allows remote authenticated users to cause a denial of service (NULL pointer dereference and daemon crash) via a crafted TGS-REQ request.

The pkinit_check_kdc_pkid function in plugins/preauth/pkinit/pkinit_crypto_openssl.c in the PKINIT implementation in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) before 1.10.4 and 1.11.x before 1.11.1 does not properly handle errors during extraction of fields from an X.509 certificate, which allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a malformed KRB5_PADATA_PK_AS_REQ AS-REQ request.

The pkinit_server_return_padata function in plugins/preauth/pkinit/pkinit_srv.c in the PKINIT implementation in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) before 1.10.4 attempts to find an agility KDF identifier in inappropriate circumstances, which allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a crafted Draft 9 request.

The kdc_handle_protected_negotiation function in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) 1.8.x, 1.9.x before 1.9.5, and 1.10.x before 1.10.3 attempts to calculate a checksum before verifying that the key type is appropriate for a checksum, which allows remote attackers to execute arbitrary code or cause a denial of service (uninitialized pointer free, heap memory corruption, and daemon crash) via a crafted AS-REQ request.

The check_1_6_dummy function in lib/kadm5/srv/svr_principal.c in kadmind in MIT Kerberos 5 (aka krb5) 1.8.x, 1.9.x, and 1.10.x before 1.10.2 allows remote authenticated administrators to cause a denial of service (NULL pointer dereference and daemon crash) via a KRB5_KDB_DISALLOW_ALL_TIX create request that lacks a password.

The krb5_db2_lockout_audit function in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) 1.8 through 1.8.4, when the db2 (aka Berkeley DB) back end is used, allows remote attackers to cause a denial of service (assertion failure and daemon exit) via unspecified vectors, a different vulnerability than CVE-2011-1528.

The lookup_lockout_policy function in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) 1.8 through 1.8.4 and 1.9 through 1.9.1, when the db2 (aka Berkeley DB) or LDAP back end is used, allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via vectors that trigger certain process_as_req errors.

The krb5_ldap_lockout_audit function in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) 1.8 through 1.8.4 and 1.9 through 1.9.1, when the LDAP back end is used, allows remote attackers to cause a denial of service (assertion failure and daemon exit) via unspecified vectors, related to the locked_check_p function. NOTE: the Berkeley DB vector is covered by CVE-2011-4151.

The process_chpw_request function in schpw.c in the password-changing functionality in kadmind in MIT Kerberos 5 (aka krb5) 1.7 through 1.9 frees an invalid pointer, which allows remote attackers to execute arbitrary code or cause a denial of service (daemon crash) via a crafted request that triggers an error condition.

Double free vulnerability in the prepare_error_as function in do_as_req.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 e_data field containing typed data.

The Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) 1.6.x through 1.9, when an LDAP backend is used, allows remote attackers to cause a denial of service (NULL pointer dereference or buffer over-read, and daemon crash) via a crafted principal name.

The unparse implementation in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) 1.6.x through 1.9, when an LDAP backend is used, allows remote attackers to cause a denial of service (file descriptor exhaustion and daemon hang) via a principal name that triggers use of a backslash escape sequence, as demonstrated by a \n sequence.

MIT Kerberos 5 (aka krb5) 1.8.x through 1.8.3 does not reject RC4 key-derivation checksums, which might allow remote authenticated users to forge a (1) AD-SIGNEDPATH or (2) AD-KDC-ISSUED signature, and possibly gain privileges, by leveraging the small key space that results from certain one-byte stream-cipher operations.

MIT Kerberos 5 (aka krb5) 1.7.x and 1.8.x through 1.8.3 does not properly determine the acceptability of checksums, which might allow remote attackers to forge GSS tokens, gain privileges, or have unspecified other impact via (1) an unkeyed checksum, (2) an unkeyed PAC checksum, or (3) a KrbFastArmoredReq checksum based on an RC4 key.

MIT Kerberos 5 (aka krb5) 1.3.x, 1.4.x, 1.5.x, 1.6.x, 1.7.x, and 1.8.x through 1.8.3 does not properly determine the acceptability of checksums, which might allow remote attackers to modify user-visible prompt text, modify a response to a Key Distribution Center (KDC), or forge a KRB-SAFE message via certain checksums that (1) are unkeyed or (2) use RC4 keys.

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 that triggers an uninitialized pointer dereference, as demonstrated by a request from a Windows Active Directory client.