Article Content
Article Number | 000037225 |
Applies To | RSA Product Set: SecurID RSA Product/Service Type: Authentication Manager RSA Version/Condition: 8.4.0 |
Issue | It has been reported that Active Directory LDAPS connections fail after an upgrade to RSA Authentication Manager 8.4.0. Symptoms include;
The Authentication Manager server ACKs, followed immediately by an Alert (Level: Fatal, Description: Internal Error), followed by a FIN.
2019-02-18 14:52:27,635, [[ACTIVE] ExecuteThread: '13' for queue: 'weblogic.kernel.Default (self-tuning)'], (LDAPConnectionTesterImpl.java:231), trace.com.rsa.ims.ldapslotmgt.impl.LDAPConnectionTesterImpl, ERROR, am82p.vcloud.local,,,,LDAP Server connection test failed javax.naming.CommunicationException: 2k12-dc1.2k12-vcloud.local:636 [Root exception is javax.net.ssl.SSLException: *Could not generate DH key pairs*] Caused by: java.security.InvalidAlgorithmParameterException: Accepted DH prime length is 2048 or higher |
Cause | Authentication Manager 8.4 is FIPS compliance for cryptographic operations (see the RSA SecurID Access Release Notes for RSA Authentication Manager 8.4), which means that 1024-bit certificates are no longer supported. However, in these customer cases the domain controller and the Authentication Manager 8.4 server both have 2048-bit certificates. However, within the negotiation of an SSL/TLS connection, the cipher suites that use Diffie-Hellman for key exchange must use a 2048-bit prime when generating a key pair. In this case, the responding SSL server (which was an F5 load balancer in front of the domain controller) responded that the TLS_DHE_RSA_WITH_AES_256_GCM_SHA_384 cipher suite would be using a 1024 prime to generate a DHE key pair. ![]() Because the F5 is using a DHE key size that is not FIPS 140-2 compliant, the Authentication Manager server errors out and the LDAPS connection fails. |
Resolution | While it may be possible to insist that an F5 load balancer or a Microsoft domain controller use 2048 prime for DHE key generation within the TLS_DHE_RSA_WITH_AES_256_GCM_SHA_384 cipher suite, RSA Engineering has developed a fix that allows avoiding cipher suites such as TLS_DHE_RSA_WITH_AES_256_GCM_SHA_384, that depend on negotiation of other cipher components such as DHE key size. This fix involves both a patch and a configurable GLOBAL variable. This hotfix is planned for release in Authentication Manager 8.4 patch 2, or customer support has a hotfix that could be applied to Authentication Manager 8.4 base. Global variable fix to avoid cipher suites that allow negotiation of non-FIPS 140-2 compliant cipher components
login as: rsaadmin Using keyboard-interactive authentication. Password: <enter operating system password> Last login: Tue FEb 26 10:36:31 2018 from 192.168.2.102 RSA Authentication Manager Installation Directory: /opt/rsa/am rsaadmin@am82p:~> cd /opt/rsa/am/utils r saadmin@am82p:/opt/rsa/am/utils> ./rsautil store -a add_config ims.tls.cipher_list.use_via_trust true GLOBAL BOOLEAN Please enter OC Administrator user name: <enter Operations Console administrator name> Please enter OC Administrator password: <enter Operations Console administrator password> psql.bin:/tmp/f8e39a3c-a614-41e3-be96-299e670f0a73525273943558510875.sql;0108; NOTICE: Added the new configuration parameter "ims.tls.cipher_list.use_via_trust" with the value "true" add_config --------------------- (1 row) rsaadmin@am82p:/opt/rsa/am/utils>
saadmin@am82p:/opt/rsa/am/utils> ./rsautil store -a update_config ims.tls.cipher_list.use_via_trust false GLOBAL BOOLEAN Please enter OC Administrator user name: <enter Operations Console administrator name> Please enter OC Administrator password: <enter Operations Console administrator password> psql.bin:/tmp/e6871864-6126-47cc-af20-0c261a3bbb643013521437038491182.sql;167; NOTICE: Added the new configuration parameter "ims.tls.cipher_list.use_via_trust" from "true" to "false" for the instance 'GLOBAL'. update_config --------------------- (1 row) rsaadmin@am82p:/opt/rsa/am/utils> |
Workaround | We did not observe Microsoft domain controllers using the TLS_DHE_RSA_WITH_AES_256_GCM_SHA_384 by default, only the F5 load balancer configured to terminate the SSL connection, and in order to reproduce this, Support had to go through a lot of configuration and manipulation to force a domain controller to use this cipher suite; therefore, a workaround would be to avoid the load balancer or configure the load balancer to pass through LDAPS connections |
Notes | This issue does not affect connections to the Authentication Manager server, only SSL/TLS connections from the Authentication Manager server to other devices, such as SMTP and SMS gateways that deliver on-demand tokencodes. See related issue AM-33242 (After Authentication Manager 8.4 upgrade SMS HTTPS plugin fails with some cipher suite)/ Also, there is no way to avoid the stricter protocol and cipher suites associated with FIPS 140-2 compliance on the Authentication Manager 8.4 servers. You cannot turn it off and use these types of cipher suites |