The error causes errors on the client site at a low fail rate: almost 100% of samples are OK and is triggered by fail over (introduced by means of server shut down);
Nevertheless, this issue occurs in clean shut down scenario (should be as smooth as possible) and floods the logs with errors producing some client side errors.
It happens in a scenario with a 4 nodes cluster where the cluster traffic is encrypted:

<protocol type="ASYM_ENCRYPT" xmlns="">
<property name="encrypt_entire_message">true</property>
<property name="sym_keylength">128</property>
<property name="sym_algorithm">AES/ECB/PKCS5Padding</property>
<property name="asym_keylength">512</property>
<property name="asym_algorithm">RSA</property>
</protocol>

The error starts immediately after the one node of the cluster is shut down and re-started affecting the other 3 nodes in the cluster; here is the complete sequence of events:

• 19:08:43 WildFly on node perf19 is STARTED
• 19:08:59 WildFly on node perf21 is STARTED
• 19:09:12 WildFly on node perf18 is STARTED
• 19:09:25 WildFly on node perf20 is STARTED
• 19:12:58 WildFly on node perf18 is STOPPED
• 19:13:00 ERROR perf19: failed decrypting message from perf20 ... javax.crypto.BadPaddingException
• 19:13:00 ERROR perf20: failed decrypting message from perf19 ... javax.crypto.BadPaddingException
• 19:13:00 ERROR perf21: failed decrypting message from perf19 ... javax.crypto.BadPaddingException
• 19:13:15 ERROR perf17: First error on the client side
• 19:14:00 WildFly on node perf18 is STARTED
• 19:15:15 WildFly on node perf19 is STOPPED
• 19:16:18 WildFly on node perf19 is STARTED
• 19:17:31 WildFly on node perf20 is STOPPED
• 19:18:34 WildFly on node perf20 is STARTED
• 19:19:48 WildFly on node perf21 is STOPPED
• 19:20:50 WildFly on node perf21 is STARTED

Here is the logs snippet (complete logs here):

[JBossINF] �[0m�[31m19:13:00,416 ERROR [org.jgroups.protocols.ASYM_ENCRYPT] (thread-27,ejb,perf19) perf19: failed decrypting message from perf20 (offset=0, length=112, buf.length=112): javax.crypto.BadPaddingException: Given final block not properly padded. Such issues can arise if a bad key is used during decryption., headers are RequestCorrelator: corr_id=0, type=REQ, req_id=18358, rsp_expected=true, FORK: ejb:web, UNICAST3: DATA, seqno=17932, ASYM_ENCRYPT: ENCRYPT [version=B6003111B71776770C2A9F8631718B7B]